Only a seller can issue a cancellation request, a buyer can only ask.
Did you receive a confirmation eBay message that your order was cancelled ?
Once eBay notify you the refund is made, being processed, then it's not instantly returned to you, and does go back to original payment source.
If you paid with PayPal it goes back to your PayPal account fairly swiftly.
Paying with a debit / bank card? Can take up to 12 days to appear back in your bank account.
Credit card payment? This takes the longest, up to 30 days to appear back in the card account used.
If you have not received any message from eBay, your item may not have been cancelled, and has been posted.
If you do not receive it, one day after the item's last estimated date for delivery open a case for item not received, and escalate on day 4 if not refunded beforehand.
@emmaoseim_23