Latest questions about "purchase error"

I have a problem with Direct Carrier Billing on Clash of Kings. I couldn't buy an in-app item. Please consider this error or suggest troubleshooting instructions.

I can't get my Samsung Billing to work. It gives me an error message when I try to purchase an in-app product. I know that my in-app purchase block is turned off so that is not the problem.

After viewing my Credit Card statement it looks as though I have been billed twice for the same program. I am not sure what happened, but I only wish to have a program registered.

I have been trying to purchase Book Librarian Plus for Windows 8 online but had no luck. I cannot download the software. I keep getting the message that the site is not available.

I want to ask why I cannot download paid games using my debit card? Charges are getting deducted but I am unable to purchase. It is sending a message that your card is denied.