We're not the developers of BreezingForms so I couldn't tell you why it may not be working, sorry. Suggest contacting BreezingForms to make sure they're compatible with PHP 8 otherwise you may need to remain on PHP 7.4 if their extension is not PHP 8 ready.
In the future please create a new topic instead of bumping a 6 year old topic to the top of the forums as it causes a lot of out of date information to be pushed to the top of the forums.