As of March 2022 I no longer accept Paypal due to their high fees. If that is really a problem for you, get in touch and I will help you out. Credit card payments are now handled by Stripe.com and their customer protection policies are just as good as Paypal. You can also use Apple Pay or Google Pay.
Express Checkout only works on (generally mobile) devices with Apple Pay or Google Pay installed.
Use your email address from any previous purchases so that they will be linked.