After backing up the site on Joomla, plugins are no longer deleted?

Question

Joomla

Today I restored the site from a backup, and now I can’t delete more than one module, when I delete one of the plugins, I get

Removing plugin: Manifest file is invalid or not found.
Error while deleting plugin.

I found this manifest file, threw it into the right folder, and after that, when deleted, it gives the following

Invalid client ID specified in manifest continuation.
An attempt was made to remove an unknown extension from a package. This extension has probably already been removed before.
Removing plugin: Manifest file is invalid or not found.

Can anyone come across and can help?