Ebay do not correspond by email.
If you have returned the item tracked, and paid by PayPal, then either escalate the case you have opened, or open one in the resolution centre and escalate it.
If you didn't send tracked and bought the postage yourself, there is no point doing anything including contacting EBay.
If the seller sent you a returns label, contact EBay as even if that wasn't tracked, you may still get a refund.
You need to use Live Chat, or phone them.
