The payment is most likely on hold but will be released.  The sale was only 2 weeks ago and you are an infrequent seller.

When the buyer opened the case did ebay send you a message saying the buyer had reached out and as it was simple delivery they would deal with it?

When the refund was made what message did ebay send you?

What reason did the buyer use for the case?

If the buyer did not use 'damaged in transit' or something like that, as the reason, then the case would not have been closed by ebay with an immediate refund of your money, that's simply not how the money back guarantee works.