Unknown error in mixamo when uploading character

[Chantel5C04]

hello! ive been having this problem for a few hours now. ive tried to upload this model so many times can anyone help 

[Ussnorway]

i confirm it wont rig even at 1.8 mb so imo its the neck or head that needs to be adjusted... you could remove the junk, make the nech longer or the head smaller?