Have you tried turning it off and on again? /slapped/ no but really, someone's had luck with restarting their computer (they were using paint tool sai v.2)
PLEASE NOTE:
This is specifically to do with wacom based tablets. Also, this journal is old, links are broken and may not be found again. My apologies.
I am not an professional in the ways of I.T or Cintiq problems. These are only the solutions I and other people have found, and they get pasted here.
if the solutions don't work for you, I'm sorry but I will not be able to help you with other things - I'm just not the expert in this. However, this journal occasionally gets updated with