Bricks Form PHP Problem

Fasthosts have been charging me for extended Linux PHP support on my bricks site. They tell me it’s because the form is PHP 8.0. I asked them to change it to 8.2. They told me that I may experience bugs after the upgrade and that I should log in to Worpress and do a WP update. But since the change to 8.2 I can no longer log in to Wordrpress. All my logins fail, I just get blank screens and on some devices the website does not even display the front end anymore or it redirects me to Betfred gambling company.

I can change it back to 8.0. but If i do then Fasthosts will start charging me for extended support again. I thought 8.0 and below is meant to be redundant which is why hosting companies charge extra for it. I would assume that the Bricks form is compatible with 8.2?

Is there some kind of update i need to do to make it work?
How do i update my Bricks form to 8.2 safely?
Are Bricks forms actually compatible with PHP 8.2?

Fasthosts are telling me i need to log into WP and do a WP update but i can no longer login, im locked out and i can reset my login. when i type into the login fields and hit return they just go blank and i get a cookies error… ‘Error: Cookies are blocked due to unexpected output. For help, please see this documentation or try the support forums.’