Add ons consistently crash world

Whenever I make a world with around 15 add ons it loads up perfectly fine for the first time and plays fine too but if I save and quit and load in for the 2nd time it always crashes no matter what and it only seems to do this with worlds that have a around 15 add ons. The only way I can avoid crashing is by closing Minecraft whenever I leave a world with 15 add ons and load back in.