The last two times I have sent out of myetherwallet I have received a red error message stating that a transaction with that hash already exists or something to that effect. Each time I regenerated the transaction and resent. Each time that transaction went through. But looking at my history the first transaction was successful! So I sent double the ETH to each address (Changelly).
I started a help ticket with Changelly to see if the funds can be recovered, but I don't have much hope. I also messaged myetherwallet to see if it is something I was doing.
UPDATE:
Looks like changelly just exchanges the additional sends automatically.
Does any body have any experience with this?