Help please Nextcloud

I have a problem with NextCloud installed on Umbrel. I updated to version 28 from 26 and it no longer starts. How do I recover the files? where are they saved? in what directory? help please

you are missing the required support template. Please fill this form out and edit into your post. This will give us the technical info and logs needed to help you in case the machine in question in spitting out errors! Since you’ve provided zero technical details it is impossible to help you as-is. Thanks.

Please use the search - lot of issues have been discussed already! if you updated directly from nc26 to nc28 you likely hit “upgrade over multiple major versions” problem see e.g. Upgrade multi major versions

familiarize yourself with the application - backup, restore and troubleshooting the application are important for self-hosting - everything is well documented-