if i missed he essential part, why don't you tell me what it is?

Fr Cole says:
Canon law quotes Canon Law saying everything proposed by Magisterium must be accepted and held. (With some qualifications that are not relevant here)
JP2 taught A
F taught B

Fr Cole asserts B=not A and asks What are we supposed to hold as true?

Logically, he should ask how can we hold both as true, since canon law says we should hold both as true. Instead he asks how do we choose between A and B? That question is excluded by the canon; if you don't hold both, you are not Catholic, according to the canon.

The usual solution is to accept that the current Pope knows what the earlier Pope said, and the current teaching somehow accords with what the earlier Pope taught. B=/= not A, a contradiction according to Fr Cole, accepted on faith in the Spirit's guidance.

Tell me what I am missing, what is incorrect. I am happy to be corrected.