got to use the foam roller daily and ITB stretches twice a day. it's gonna take a while to clear up, maybe months. be diligent even though the roller hurts, do it. you don't have to do it more than a few minutes a day.

what caused mine was an epic 3+ hr dumb ride in a 20 degree snowstorm on new year's eve a couple years ago. used my newly built tank MTB with studded MTB tires aired down too much, used too high a gear, seat was too high and my ITB was too cold for too long. those 3 things, gear too high, seat too high, temp too cold, bingo whamo there ya go. took months to get me to try a roller then a couple more of actually using it with proper stretches before I was free and clear of the syndrome.