Sorry unable to map your existing skeleton

I had downloaded the companion bot 3d model from the game stray adjusted it a little and have been trying to upload it to mixamo but it fails to do so. Initially I was able to upload the same and the animations were decent enough i decided to tweak the bones a little and the file just stopped uploading . any help is appreaciated thanks 

https://we.tl/t-L0CTfCWXLg