Minecraft crashes whenever I try to upload a custom skin.

I've tried everything to fix this. I uninstalled and reinstalled the app, and I followed what people said to do for this issue online, but nothing is working. I recently factory reset my tablet and bought MC on a new email, yet it worked before I reset my device and while I was using my old email. Why does uploading a skin suddenly not work? (I'm using a Next book Ares10A Android tablet running Marshmallow.)