If a return is for change of mind and you have a stated refund policy with exclusions for specific situations, such as returned beyond refund policy date, returned out of sealed packaging if that was specified, returned damaged by buyer or any other reason allowed by law, OR if you simply don't accept change of mind returns, then there is no way that ebay or paypal can force you to refund under those circumstances.
If paypal refunds the buyer without your consent for such reasons, then contact paypal and demand that they return the funds and if they refuse or give you the run around, then report them to the FOS.
https://www.fos.org.au/resolving-disputes/before-you-lodge-a-dispute/
If the buyer has opened up a not as described dispute simply to force a return for fraudulent reasons that they may not be entitled to, then contact paypal and provide them with as much evidence as possible that the dispute is not correct.
An example may be an admission in an ebay message or email that they simply bought the wrong thing prior to them complaining that it was not as described.
In that case also notify the buyer that what they are doing is fraud and will be pursued as such through legal channels.
If you have provided a return policy that includes change of mind purchases for any particular reason then you are obliged to honour that refund policy.
It is illegal to state that no refund will be provided under any circumstances because buyers always have the right to a return under common law provisions such as faulty, not-as-described or not fit for advertised purpose.
We have had many return situations for all sorts of reasons and have applied the above advice in every case and so far we have always received refunds from paypal where a refund was applied when it should not have been or was not authorised by ourselves.
