Snapshot again not working

Hello,

scheduled Managed Backups are not working, instant Backup also not. It seems the site is loading forever and then the process stops:
https://www.evernote.com/l/AAPDF7kxA4pLj4-sqM_wQBhnpeZqwYeKWSM

Is that a server or plugin issue?

Thank you and kind regards,
Sascha