Cancelled, payment for buy by mistake

[lorraine000]

I sold an item on ebay, the buy contacted me to say the payment had been cancelled and couldn't understand why.

I checked my  paypay account which said 

payment complete, cancelled, issue refund.

1)  can I reverse this cancellation. Or 

2) if I don't issue refund and still send the goods would that be OK? Will the money in my paypal account be avelible for me to withdraw

the buyer still  wants the goods, I haven't a clue how this has happened but I'm sure its my fault as I'm new to ebay and paypal

[snowshoe]

You need to start over.  If you don't and something goes wrong either with you or the customer, it could be a mess if there is a claim or dispute.

[lorraine000]

what should i do? issue refund then how would I go about gettting payment again