I have been having a lot of trouble with the paypal module on my current website which used to work fine. When a customer uses the express paypal button they get taken to the paypal site of which they sign in but when they return to the site the basket is empty, they then continue to pay via paypal and continue this loop indefinatly. When checking the payment module logs the individuals attempting get SetExpressCheckout and GetExpressCheckout repeatly and from what I have read a completed authorisation process must send back a DoExpressCheckoutPayment. I tried updating the version which worked at first as I tried to process a payment for myself as a test but then the problem started again just as before and now no payments are processing for people.
I have no idea what this could be, if anyone could assist in this problem it would be amazing.