OnlyOffice connection lost to server

Hey Team,
we use OnlyOffic Version 7.6.8 an when we open any Dokument we get an time out “connection to the Server lost”.
Cloud you please help do fix it!

Thanks
Wolfgang

Hello @it-verwaltung

Please double-check the version or please specify to which ONLYOFFICE product it is related.
Also, please provide any screenshots of errors from editors interface and error entries from browser console while reproducing this issue.