I'm sorry to hear that keeps happening! If you think you've found a bug, please visit bugs.mojang.com/secure/Dashb… and report it so that the developers can see. ^AS
I'm sorry you're having trouble! Please send us an email at help.minecraft.net/hc/en-us/… and we will assist. Remember to attach your Transaction ID in your response to us, if possible. ^AS
Sorry about any delay you're encountering! We try to respond to tickets as quickly as possible in the order they were received. We appreciate your patience! ^JR