Some people have been having issues. PayPal have reached out with the following.
After the investigation, I found the transactions are declined due to risk. We found that guest checkout or pay with debit or credit card payment, and buyers don’t always have the option to complete their purchases without using or creating a PayPal account. This option is presented based on several risk factors, including but not limited to the buyer’s PayPal purchase history, PayPal cookies stored on the buyer’s computer, the buyer’s location, or a credit assessment.
Also, we have analyzed your payment received preference and could find that the Guest Checkout (pay with credit cards) option is enabled on your PayPal account. It’s important to remember that guest checkout is not guaranteed for every transaction processed on PayPal. This is an intended behavior of guest checkout functionality.
Note: PayPal runs a risk check to determine eligibility for guest checkout on country, location, and IP address of the customer machine/devices, etc. If your customer/machine passes the risk check, then they can able to process a guest checkout option.
Once the customer is redirected to the PayPal Checkout page where they will get an option to create a PayPal account with a direct card option (OR) customer can log in with their PayPal account.