I have received an unknown charge related to a recent sale. How can I find out what the charge is f

[cons_treasures]

I recently sold an item on Ebay for $200.  I received a paypal payment of $194.50.  I was then charged an additional amount of $21.78.  Can someone pleae tell me what this fee relates to?

The Receipt ID: B-3Y893568KR489562N 

Thank you.

Sue Connell