The joint is stuck by paint sometimes (usually issue on action figure)
We may warm it up by the steps suggested
1) pull out the peg before warm it up
2) inserting the peg to lower part body first without torso
3) put back the torso
4) put the upper body on top of peg
We have launched a FaceOff program to who have purchased 002/010/017 figure in 2019 thru Kickstarter or official retailers.
Here are the steps: