Buyer claims they never received refund and have created dispute even though refund was given.

I am currently experiencing an issue that I have never experienced before.

Almost 2 weeks ago a buyer purchased two items from me, both separate transactions.

Before sending the items I noticed one item wasn't as described and notified the buyer and gave them the option of a partial refund or to cancel order to avoid any hassles once they had received it.

The buyer chose a partial refund and I shipped their order.

I refunded the buyer twice, one partial refund for item not as described and another for excess postage paid as I combined the shipping - so both items purchased received a partial refund.

This order was delivered and a few days later the buyer contacted me saying they hadn't received their refund back to their Paypal account.

I responded and let them know they had been refunded and sent them a screenshot of the notification eBay had sent me confirming that the refund had been completed.

They responded a few days later telling me again they still hadn't received their refund, this time, to their bank account.

I told them I had refunded them and said I didn't know how to help them any further and it would be best if they contacted eBay regarding this issue.

The next day they had created two separate disputes with eBay claiming to never have received a refund.

I have challenged both disputes and provided evidence.

This situation has not sat well with me and it's been bothering me for days.

I then contacted the buyer asking them to please clarify where the funds had to return to as there could be an issue with their Paypal or perhaps they were not aware that the funds were in their Paypal account and they would need to be transfered to their bank account.

They responded saying they had received nothing to their Paypal account.

This is bizarre to me as they would have received a notification from eBay once I initiated a refund.

I always get one when I refund, so naturally the buyer would receive one too.

The buyer said they had received no notifications.

I have triple checked my eBay transactions in my seller hub and the refunds were definitely processed as I'm minus the amounts refunded.

I feel this buyer is trying to scam me and double dip with receiving a second refund.

The thing is, they received two refunds however they were only aware they were receiving one as there was no communication regarding them receiving a refund for excess postage, yet they created two disputes.

So how can the buyer say they didn't receive any notifications?

I asked them how did they know about the second refund and they said it was a different seller for similar amount - I don't believe this.

The big problem with this whole situation is now my sales have fallen off the face of the planet with none since Thursday and I've been listing every day.

I hate disputes because they interfere with your eBay algorithms, and I'm unfairly being punished for something that is not my fault.

Has anyone else experienced this?

Should I escalate this further with eBay?