This happened to me as well and the only eartips that have worked for me are these AZLA eartips
They are made out of this special polymer that are much “stickier” then silicon, or rubber. It also doesn’t rely on pressure to keep them in (like foam) so it doesn’t have as much pressure on your ear drum.
I’ve tried over 10 different types of earbuds tips and these are the only ones that have worked. The only downside is that they do wear out more often then other materials but I’ve accepted that as a trade off for finally getting the AirPods Pro 2 to work for me.