@MojangSupport Have 2 children. Purchased about 750 Minecraft coins on my MS account for both of them (have proof of purchase). Went into my daughter's Minecraft, purchased a few items of clothing....a few mins later - no coins left!
My son got nothing - and no coins left either!
Please send us an email at https://help.minecraft.net/hc/en-us/requests/new … and we will assist. Remember to attach your Transaction ID. ^AF