Unable to pay by credit card

You might need to check your PayPal Account Optional setting.

Paypal:

When PayPal Account Optional is turned on, your customers who are new to PayPal will no longer be required to create a PayPal account to complete a purchase—they will go through an alternate checkout, and will have the option to sign up afterward. Customers who already have PayPal accounts will continue to enjoy the privileges of those accounts, such as payment history and integration with eBay Auctions, and their checkout experience will remain the same.

This feature is available for Buy Now, Donations, and Shopping Cart buttons, but not for Subscription buttons.

Note: If you have turned on Auto Return and have chosen to turn on PayPal Account Optional for new users, a new user will not be automatically directed back to your website, but will be given the option to return.

Hello Peterfz30,
I am also having this issue and called paypal, they told me it is a paypal issue and they are working on it. They cant tell me how long it will be down but to ask my customers to click on Sign up and it is taking them to the guest checkout of paypal where they can enter the credit card. Nicole

Thank you Nicole,

I rang PayPal again and they confirmed that they have an issue and it should be resolved within 72 hours.

Seems a rather long time.