An apology with no change attached is just a notification. It doesn’t open anything.

An apology is a claim about what happens next, not a summary of how you feel. With nothing different attached, it costs the speaker nothing and leaves the other person exactly where they were, now also expected to be satisfied. That is why repeated apologies for the same thing stop working: people are not tracking words, they are tracking the pattern. Sorry is the opening move rather than the whole thing.

Next time you owe one, name the specific thing you will do differently, then do it once, visibly. Skip the explanation of why it happened.