world conversion issues

I'm currently trying to transfer a 320.8 mb world that was made on 360,then transferred to xbox one edition, to bedrock edition on xbox one but every time the world conversion gets to about 87 percent my game crashes and sometimes it glitches out my xbox to where ive had to hard reset, ive tried every trick i know to fix it but none work, help would be thanked

(sorry for spelling or grammatical errors)