Perhaps someone can advise me. I am running an application (ZenCart) successfully. I have a development version of the same site running on a separate server to work through the issues of php versions. Paypal Express has worked fine on the site for many years. I am in the process of fault-finding the installation on the development site. When I attempt to initiate a connection I receive an "invalid amount" response like this:
Can someone advise whether there is some other cause of this response - for instance, either an authentication error or a Payflow error of some type? Also, is there a way of finding further information about the response? Can I contact Paypal and simply ask them why this response was generated? If so how?