I need help with my broken texture for json model

Hi i am trying to make a really cool hammer that i want to have a 3d model but the problem is its rendering it as a purple black cube. I dont know why i have tried every single page i have seen and have seen the knowledge base and nothing. If somebody knows how to fix it please help.
P.S.
If i find the problem i will tell everyone that also has the problem just type here that you have it.