Unable to join world while it has add-on

Every time I try to join my friend the required download size is 100 plus mb but it doesn't show it at allar the same time I get put on 0.10mb it takes a minute and then says failed it's not my internet or everything else is wrong just crashed when the size is too big.

It's a decent about of 9 but a player should be able to use a large about if they want.

I don't have a screen shot because I'm trying with my friend to fix by downloading them again it's very frustrating trying to fix it should just download no problem