Minecraft crashes trying to load a blockbench model using sub bones (Solved)

I'm probably just doing something wrong but I'm gonna ask about this anyway.

I created a model for a mob in blockbench that uses sub bones and now whenever I try to playtest the mod it crashes on the loading screen

https://youtu.be/p2zg49qqJW8

Please help me I have been stuck on this for way too long

I should also say it worked fine without the sub bones, the only issue as the arms and legs pivoted off the wrong end

Issue has been solved