Hello, right now it appears your account is correctly set up to accept checkout payments using PayPal Payments Standard, which appears to be working fine for you.
PayPal Standard checkout does not have a Proceed to Pay button, so I'm thinking previously you'd also enabled another payment gateway to accept direct card payments, which may not have been fully set up properly. If you wanted to try setting that up again, make sure you follow our setup instructions for that service, linked from here: