this is why reputable exchanges do not accept paypal/credit cards. due to what has been known for years as "chargeback scammers".

yes visa and mastercard have actually themselves banned purchases of bitcoin via their credit cards,
as has paypal not being helpful to bitcoin sellers
not due to 'protecting customers investment risk' but actually to protect visa/mastercard from the costs of fraudsters doing chargeback scams. because it became soo rampant.
visa/mastercard/paypal wont fully admit to this. because that then is advertising a flaw in visa/mastercard/paypal that anyone can use to get their goods and their money back.. literally would cause a bank run of scamming if everyone knew/done it