Canonical Answer for "my payment went through, but the sender is not acknowledging it"

Question

I just answered Bitcoin successfully deducted on sender wallet but did not reached receiver wallet, and I think I've seen a few similar questions in the past months.

Let's collect similar topics here, then pick or write a canonical question so that we can close the others and future duplicates in its favor.

Answer 1

RedGrittyBrick just wrote an epic answer on a duplicate question here: https://bitcoin.stackexchange.com/a/93149/5406. I'm proposing that we'll move them all onto one question.