Basically I made a custom rig but for some reason it freezes when I run the game and whenever I anchor then quickly unanchor him he just starts flipping and becomes unable to stand up.
Looks like its made out of unions, do you think it could have something to do with its collisions? At the beginning of the video, You checked its state, and the output was falling. I don’t think it ever left that state, but it was on the ground. Since there is only so much falling one can do on the floor, it was flopping around. This could also be because it didn’t know how to stand up due to collisions (or perhaps a hip-height that was too big or small).
Other issues could be that your rig hierarchy is in the wrong order.
also
Do you have 3 torso parts? (If you are trying to make this a classic r15, then you will need to rename the upperTorso as such (and maybe merge the middle to the lower torso)
Don’t forget to set HumanoidRootPart as a primary part of the model, and inside Humanoid edit the hipHeight ( or something like that ) to desired length in studs ( this value should be the length between the bottom of torso and the ground, so in classic r6 rig that value is equal 2 ). Additionally, you might want to check Roblox API on how the humanoid parts named exactly in different rigs. Sadly cant provide with the link.