I'll point you in the right direction for support concerning the issue you have with PayPal.
We have an ongoing investigation of this specific issue. I suggest you contact our Technical Support team for assistance. What they can do is add you to the list of our affected users. And with that, you'll receive an email notification whenever an update is available.
Log in to your QuickBooks Online (QBO) company.
Click the Help menu.
Select Contact us.
Here's an article with a list of common questions about a specific feature from PayPal: Accept Card Payments with PayPal app FAQ. The long list of questions come with answers, which you can use as a reference.
Feel free to post a comment below if you have other questions. I'll get back to you as soon as I can.