Hello Britannia0305-ou, thanks for reaching out about leaving an accountant review. Are you referring to the accountant directory that you cannot find the accountant on - Find a Chartered Accountant Near You | QuickBooks UK (intuit.com)
Regarding deleting the accountant user, Is the accountant in your manage users section also the master admin on the accountant? If so, you would need them to transfer the master admin access to you first and then accept it before you can remove the accountant user.
If that is not the case and you are the master admin, could you try opening QB in a private window and removing the accountant user, does that then work?