Replying to Full Tilt Classics

I have been using the Full Tilt classics for three seasons now, I was fitted at a regular shop and not by a professional boot fitter, nevertheless they initially fitted quite well.

I fit in a size 9 shoe loosely and an 8.5 shoe snuggly, so I found that the 26.5 size fit me the best and the classics narrow shell size also fit my narrow foot.

I have not heat molded them in a very long time but I was wondering if I should get a aftermarket footbed or a custom footbed because my heel seems to be moving around and it feels like there is a lot of lateral lag left to right.

What should I do to fix this problem, will heat molding fix it?