Not the OP, but I have the same issue. Tried the 3 original tip sizes as well as 3rd party foam tips - no use, they either hurt after a short while or don't seal properly, causing ANC to barely work at all and the headphones to fall out when jogging or doing exercise. Guess my ears are not shaped for the Pros, or any in-ear earbuds for that matter - it has always been the same story with any brand I tried over the years.

However, the 1st/2nd gen "base" AirPods are a perfect fit for me, so I just ordered a new pair to replace my 3 years old 1st gen with almost completely failed batteries. Would've used something like Podswap, but unfortunately no such service is available in my country that I could find.