OnlyOffice documentserver 404 error

I installed Onlyoffice via “Apps” in Nextcloud and enabled it. Nextcloud was installed via docker-compose.
In Administration settings → Only office → I need to enter “Onlyoffice Docs address”. What is it? I didn’t install it separately, just by Nextcloud’s apps in dashboard. My Nextcloud address isn’t working.

Hello @salamander,
It is not enough to just install the ONLYOFFICE app in Nextcloud to enable document editing. You need to install the Document Server first. Please take a look at the guide:

Document Server installation guides are available here: