What does your running technique look like?
This could be a contributing factor.
A deviation in running technique may be the cause.
Have you looked up/down stream of where you experience the issue?
Episode 142: Tight IT Band and Hip Flexor Fix: Runners?
Episode 61: IT Band Hell, And Help…
Pro Episode # 36 – Voodoo Floss Series # 3: The High Hamstring
Pro Episode # 35 – MWod Pro-User Request Friday: The IT Band Primer
Episode 361: Pathomechanics and IT Band Hell Part 1
Episode 361: Pathomechanics and IT Band Hell Part 2 Episode 361: Pathomechanics and IT Band Hell Part 3
How often are you working on this. Where it isn’t a new issue you probably want to start with 2 sessions a day.