Can't update or cancell other plugins

Searching the text “Security check, invalid access” on the Internet [1] returns a list of similar tickets created by other users in the “WP Database Backup” plugin forum, that message is not part of the Sucuri WordPress plugin so I suggest you to contact the “WP Database Backup” [2] developer to see if there is something they can do.

If you can provide more details about the issue in case that you still believe this is caused by the Sucuri plugin then I will investigate further, but the problem seems to be in another plugin, so I will mark this ticket as resolved for now, feel free to re-open if necessary.

[1] https://www.google.com/search?q=%22Security+check%2C+invalid+access%22
[2] https://www.ads-software.com/support/topic/warning-security-check-invalid-access