Page Hacked - Admin Access

Hi all, to a cut a long story short, someone has somehow managed to get admin access to my page and I can't remove this as it keeps coming up as an error.

When I go through the business manager settings, this comes up:

You do not have permission to perform this action. This action requires that you can MANAGE_EMPLOYEE_LIST for this business account.

I have no idea what they've done but I can't even go through FB support to flag it because it says I don't have any pages even though I'm still an admin to this page and 2 others.

Does anyone have any ideas as to what I can do?

Capture the role on the page

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