A guide to resolving the problem on steam where "Your purchase has not been completed. The payment processor has reported an authorization error. Please select a different payment method"
If you have been using paypal to make a few purchases, and have recieved this problem, you’ll first need to know what exactly the problem is. The problem is that your account has been flagged by steam for fraud, due to multiple purchases with paypal. Steam will require you to confirm your identity and prove that you actually own the steam account and the Pay Pal account. Many people experience this problem during an anual steam holiday sale, so don’t be too worried. However there are steps you can preform to resolve this problem.
Contact Steam Support:
An important thing to do right now will be to contact steam support to notify them of the problem. If you don’t already have a steam support account, be sure to create a new one in the steam support page (your steam support account is seperate from your actual steam account, similar to your steam forum account). Then select ask a question from the top of the steam support page, enter your information into the page that follows, and select your category as “purchases and payment”, and then “Pay Pal”. If you were trying to purchase a product, select it from the drop down list and then prepare your question. Explain your problem, as well as any steps you had taken to resolve the problem. Provide information on the games you tried to purchase (names, prices, special deals for the day). Be sure to describe the problem in detail, providing as much information in the first message will help steam support to resolve your problem ASAP. Also provide information about your steam account to prove your identity, and also a random piece of information that makes your account unique (like if you purchased a certain series of games in a certain order). Finally the information steam support really needs, to help you resolve your problem. In a seperate paragraph from the other information include: The steam account name you are trying to purchase on, Complete paypal account holder information (name and address [your full billing address and your full name which you gave to Pay Pal]), a valid daytime phone number along with the area code and country code (if applicable). Once a steam support staff member reads this information and verifies it, they will notify you and you should again be able to purchase again. Also, if you happened to miss a special deal because of this problem, be sure to ask for a discount for the games you tried to purchase. You can also provide proof by going to the main steam website, logging into your account, and then going to your account page where steam lists the games you have, as well as how much you bought them for and any failed purchases. If you attempted multiple times to purchase a game, but were unable to because of the problem, take a screen shot of the page, paste it into paint, save the image as a JPEG (or other image format), and attach it with the question. With luck, the problem will be resolved and you might also recieve a discount.
As a workaround, if you are really desperate for a certain game, you can utilize another account (or create a new one), gift the game to your self by E-MAIL, purchase with the same payment method, and then simply accept the gift from your e-mail account.