The same issue happened to my server. I hope this helps
[1884.87] DevOnline: UOnlineGameInterfaceSteamworks::RefreshPublishedGameSettings(): GameTag string: d:7,e:4,a:1,l:0,m:1,k:0,i:2,n:0,h:0,b:0,c:0,p:0,f:0,
[1884.87] DevOnline: Advertising: SteamEngineVersion=10897
[1884.87] DevOnline: Advertising: OwningPlayerId=0
[1884.87] DevOnline: Advertising: NumWaves=7
[1884.87] DevOnline: Advertising: CurrentWave=4
[1884.87] DevOnline: Advertising: bInProgress=True
[1884.87] DevOnline: Advertising: bMutators=False
[1884.87] DevOnline: Advertising: bCustom=True
[1884.87] DevOnline: Advertising: bAvailableForTakeover=False
[1884.87] DevOnline: Advertising: ZedCount=10
[1884.87] DevOnline: Advertising: MaxZedCount=100
[1884.87] DevOnline: Advertising: MapName=KF-TRAGICKINGDOM
[1884.87] DevOnline: Advertising: Difficulty=2
[1884.87] DevOnline: Advertising: Mode=0
[1884.87] DevOnline: Advertising: NumSpectators=0
[1884.87] DevOnline: Advertising: NumPublicConnections=6
[1884.87] DevOnline: Advertising: NumPrivateConnections=0
[1884.87] DevOnline: Advertising: NumOpenPublicConnections=4
[1884.87] DevOnline: Advertising: NumOpenPrivateConnections=0
[1884.87] DevOnline: Advertising: JoinString=94.59.186.69:7777
[1884.87] DevOnline: Advertising: bShouldAdvertise=True
[1884.87] DevOnline: Advertising: bIsLanMatch=False
[1884.87] DevOnline: Advertising: bUsesStats=False
[1884.87] DevOnline: Advertising: bAllowJoinInProgress=True
[1884.87] DevOnline: Advertising: bAllowInvites=True
[1884.87] DevOnline: Advertising: bUsesPresence=True
[1884.87] DevOnline: Advertising: bAllowJoinViaPresence=True
[1884.87] DevOnline: Advertising: bAllowJoinViaPresenceFriendsOnly=False
[1884.87] DevOnline: Advertising: bUsesArbitration=False
[1884.87] DevOnline: Advertising: bAntiCheatProtected=True
[1884.87] DevOnline: Advertising: bIsDedicated=False
[1884.87] DevOnline: Advertising: bServerExiled=False
[1884.87] DevOnline: Advertising: bRequiresPassword=False
[1884.87] DevOnline: Advertising: bCloudServer=False
[1884.87] DevOnline: Advertising: OwningPlayerName=Balanced KF2 Server (CD) - Multiple Bosses
[1884.87] DevOnline: Advertising: PingInMs=0
[1884.87] DevOnline: Advertising: MatchQuality=0.000000
[1884.87] DevOnline: Advertising: GameState=OGS_NoSession
[1884.87] DevOnline: Advertising: BotPlayers=0
[1884.87] DevOnline: Advertising: SteamServerUID=90146975419211780
[1884.87] DevOnline: Advertising: SecondsDeallocated=0
[1884.87] DevOnline: Advertising: SecondsDeallocatedBucket=0
[1884.87] DevOnline: Advertising: Region=USCentral
[1885.72] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1886.75] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1887.74] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1888.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1889.75] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1890.74] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1891.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1892.72] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1893.74] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1894.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1895.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1896.75] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1897.74] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1898.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1899.72] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1900.75] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1901.74] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1902.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1903.75] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1904.74] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1905.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1906.75] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1907.74] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1908.73] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1910.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1911.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1912.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1913.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1914.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1915.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1916.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1917.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1918.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1919.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1920.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1921.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1922.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1923.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1924.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1925.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1926.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1927.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1928.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1929.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1930.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1931.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1932.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1933.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1934.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1935.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1936.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1936.80] DevOnline: Sending out playfab request to url Server/RefreshGameServerInstanceHeartbeat with data: {"LobbyId":"11759804788073118050"}
[1937.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1938.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1939.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1940.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1941.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1942.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1943.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1944.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1945.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1946.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1947.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1948.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1949.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1950.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1951.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1952.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1953.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1954.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1955.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1956.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1957.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1958.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1959.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1960.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1961.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1962.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1963.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1964.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1965.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1966.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1967.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1968.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1969.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1970.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1971.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1972.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1973.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1974.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1975.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1976.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1977.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1978.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1979.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1980.58] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1981.57] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1982.56] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1983.55] ScriptLog: Partial squad spawn: unable to spawn 7/0
[1984.57] ScriptLog: Partial squad spawn: unable to spawn 7/0