Hi Manu2020,
Thanks for coming to Apple Support Communities for help today.
If you can't verify PayPal as an Apple ID payment method, you will need to contact their support for help: PayPal Contact Us.
The other option is adding a different payment method as described here: Change, add, or remove Apple ID payment methods.
"How to change your payment method on your iPhone, iPad, or iPod touch
- Open the Settings app.
- Tap your name.
- Tap Payment & Shipping. You might be asked to sign in with your Apple ID.
- From here, you can do these things:
- Add a payment method — Tap Add Payment Method.
- Update a payment method — Tap the payment method, then edit your information. You might need to enter the security code that's printed on your credit or debit card. If you use the card with Apple Pay, go to the Wallet app to edit the card information.
- Remove a payment method — Tap Edit, tap the red Delete button, then tap Remove. If you have an unpaid balance, have subscriptions including an iCloud storage plan, or you use purchase sharing, you can't remove all payment methods. Learn how to remove all payment methods.
- Change the order of your payment methods — Tap Edit, then drag the move order icon ."
If you are unsure what other types of payment methods can be used, please see: Payment methods that you can use with your Apple ID.
Have a fantastic day!