Mine was corrected...
This is what
Joel R 3,104
Told me and it worked...
PayPal Settings
It looks like you have your PayPal settings correct. However, you're not able to use PayPal on certain transactions (such as Donations) without the customer's real name and billing address. This is probably why your users are receiving an error, because PayPal is your only payment method.
Go to ACP > Commerce > Payments - Settings
Click on "Payment Methods" tab. Verify PayPal information is correct.
Click on "Checkout" tab. You need to enable on all three choices for "Require customer's real name and Billing Address when"
Other recommendations
Enable Stripe as a payment gateway for backup.
I also added the Stripe as recommended and received a payment via it two hours later for merchandise...