@builder3 This isn’t a PayPal issue at this point. Hire an attorney, he’ll send an official letter.
Disputes may be opened with Paypal within 180 days of the payment date (August 2021). Then there is a timeline to follow.
In any event (it appears that the OP has been reluctant to do that - the 180 days must be around now, or very very soon) I have previously advised to consult with a qualified legal person who yes, would probably shoot off a letter of demand. Something any retail lawyer is familiar with.
Easy.