Adjustable golf club too tight

[MadAdey]

When you do get it off , take head off completely and just check the head and adapter for debris, swarf off the threads .
Before you put it back together put some just a little WDF or Vaseline on the adapter this will stop it sticking.

Whenever I take the head off my club to have a play around with settings I always clean it out with some WD40 as if you get a bit of dirt drop in there it can start acting like a thread lock and cause the original posters problem.