I think the two items were returned on 21st, December, but No. A returned to me again. Does that mean No. B was successfully returned to the seller? Could you let the seller know that only one item was not returned?
Does this mean that the number A came back again and the number B is back at the seller although both of them were sent back to the seller on 12/21? Is it ok to inform to the seller that one of them hasn't successfully been able to be sent yet?
I thought I returned 2 items to you on the 21st December. Does it mean that number A has been returned back to me and that number B has been returned to the seller? Should I just tell the seller that only 1 item has been returned?
12/21 => Dec. 21 にしてください。