Nextcloud 30.0.2 Integrity Check error

Hello,
I updated Nextcloud to version 30.0.2 (it runs on a Ubuntu server 24.04.1 LTS x86_64) and now I have an integrity check error:

  • mail
    • EXCEPTION
      • OC\IntegrityCheck\Exceptions\InvalidSignatureException
      • Certificate is not valid.

Raw output
Array
(
[mail] => Array
(
[EXCEPTION] => Array
(
[class] => OC\IntegrityCheck\Exceptions\InvalidSignatureException
[message] => Certificate is not valid.
)

    )

)

I saw that mail app cannot be uninstalled and reinstalled. How can I solve this problem?

Thanks

Duplicate of Mail-app failed the integrity check after updating

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