Can not buy. Products in the game. Then the words "Your Purchase Could Not Be Completed. For assistance, contact iTunes Support at www.apple.com/support/itunes/ww/." Please tell me how to solve it.

If you haven't already done so contact iTunes Support as instructed to do by the message (these are user forums, not iTunes Support) :

- go to http://www.apple.com/support/itunes/ww

- click on your country's flag (the country where you are, and which is therefore the country on your account)

- click on Contact Support towards the top right

- click on Get Help under 'Talk To Us'

Or use this form : https://www.apple.com/emea/support/itunes/contact.html