Change Gmail account to make in-app purchase?

What is the procedure to change email account which you want to use to make in-app purchase? Take a look at the image. Click to enlarge the image I am using 2 Gmail accounts and only 1 has a credit card attached. The primary account has a credit card, the secondary does not. But my secondary account is always in the payment dialogue. The secondary account is also not the account used in Play Store app. I found no way to change this email.