Cannot open the dressing room button, Opening MarketPlace crashes the app.

Hello, This is about a bug that i'm experiencing that if i open the marketplace of the minecraft, the whole thing crashes, Also i cannot open the dressing room. I Don't know if this connect the issue regarding my friends that cannot join to my world. One time it worked, i don't know what fixed it but i connected to another router on my cousins house. but it started not working again. Another one is that i cannot join the servers like Hive, its say's that i cannot validate my login. if its possible, can u tell me what is the problem and how can i fix it? Thank you!