How do I get a refund for postage I paid through eBay/paypal that would not print and was not used?

[codmac]

How do I get a refund for postage I paid through eBay/paypal that would not print and was not used?  At the time I bought this postage, it would not print because the

Firefox upgrade did not recognize Adobe Acrobat 4 and could not open it to print, so I bought new postage using Chrome.  I since then installed the Acrobat update.  I paid for both the original I could not print and the second one through paypal and need tp get a refund of the first, $33.96.