ONLYOFFICE cannot be reached. Please contact admin. After update 29 to 31

I have Nextcloud version 29 and Onlyoffice deployed in Docker. Everything worked fine. After updating Nextcloud to version 31, Onlyoffice stopped opening documents, while the settings are available and the connection to the Onlyoffice server is error-free. Updated Onlyoffice connector to version 9.8.0. The error persists