Nextcloud (and mainpage) crashed during upload of files

Hi all,

I’ve instaled Nextcloud as a subdomain with his own database, the provider is

Everything is working well, accounts could be created and all the apps are logging in.

Then the part of uploading files.
The upload works well, takes a lot of time with my 20MB upload line.

Only after a while, when there is 37GB is uploaded (different files in different directories) the whole site crashed.

I had to restore my files and database, started over with uploading the files and again it crashed.

Who has expierence with as hosting platform?

Kind regards,