Wouldn't it be easy to just reset my account or something? I have even tried to change countries (I have billing and cc valid in 2 different ones) and nothing. I reported this issue 6 times in different emails. The girl from Apple store is not helping at all 😟 She keeps copy/pasting the steps to update my billing and phone on the website, I did it more than 30 times now. I update my Credit Card to a new one (I tried 3 genuine ones) and it says to contact support all the time. I have a pending payment of 3,99 Eur and it says to update my billing info. I was able to make this work with two separate itunes accounts with two different accounts so I dont think it was a fluke. Choose 'Done' and then login to your itunes account on the problematic device and retry. Re-enter the 'Required' Security Code field along with verifying the remaining fields. Sign in as requested after choosing 'Continue' and then tap your 'payment info' box. To remedy, I went into the iPhone Settings -> Store -> View Apple ID I believe (from what I have read) this is an issue with multiple devices sharing an itunes account. I was attempting to purchase music from the iTunes store and upon the review of billing information it provides the ominous message 'Please contact itunes support to complete this transaction' which people are seemingly having no luck with. Keep in mind I am an iPhone user and make purchases via mobile on the itunes store which I think is related to this issue. I fussed with this problem for a couple hours and had success with the following workaround.

Apple itunes support number