If there is still a problem after that, and it says the service is not active, then there may be a data mismatch somewhere between your account, and the exchange equipment number, and a moderator can be asked to help.
The PAYG is now the default for all new renewals. I assume you must have added one of the calling plans yourself?
If you had not done that, then you should be able to select one of them yourself.
I was on the 700 minutes per month plan and didn't ask for any change to that. That was only a new package I joined around September 2020 when I changed over to the Halo product.
That may have been removed when you changed over to FTTP, you may not have noticed it.
BT now assume that many people only use the landline occasionally, or not at all, so it makes sense to have a PAYG option. You will have to decide what is best.
I am on an old legacy ADSL (12Mb) package, which has free weekend calls, however I cannot remember the last time I made a call, as its my wife that does that, and she has unlimited calls on her BT mobile.