For IP error pop-up or invalid IP address provided (PayPal returned API error code 10747/ Invalid Data) -This transaction cannot be processed without a valid IP address.
As part of the DirectPayment API request, PayPal requires merchants to capture and send the buyer's IP address. This error occurs because the IP address is in an invalid format.
Check the IP address and make sure it is in the IPv4 format, using the dotted decimal notation of four integers, each ranging from 0 to 255. An example of an IP address in IPv4 format would be 126.96.36.199.
IPv6-format IP addresses aren't currently supported.