How long ago was this? I'd be surprised to see Claude 3.7 Sonnet make a mistake of this nature.
Either way, when a model starts making dumb mistakes like that these days I start a fresh conversation (to blow away all of the bad tokens in the current one), either with that model or another one.
I often switch from Claude 3.7 Sonnet to o3 or o4-mini these days. I paste in the most recent "good" version of the thing we're working on and prompt from there.
Not actual knowledge but adages ! Lol "here is my magic potion that I can't tell you how it differs from the other magic potion!" That is not fixing anything. That's trying to string people along and insert yourself otherwise you'd be able to point so some kind of empirical documented experience as to why one vendor is better than the other or why older models have the problem but newer ones don't, and more importantly assurances that future models or even future unannounced changes to the models you mention will even work the same as they do today. What knowledge are you actually imparting other than "I think this is a road you could try." Thanks.
Lol, "it didn't do it... and if it did it didn't mean it... and if it meant it it surely can't mean it now." This is unserious.