Windows 10: how can I get my credit card details for the last 4 numbers to verify it is my account

how can I get my credit card details for the last 4 numbers to verify it is my account

:)

 

credit card details already exist

Two things you can do.

• Visit commerce.microsoft.com and then head over to the billing section. Remove any credit card details that may exist and make the card section completely empty. Then head to windowsphone.com and then try to buy the app and it will prompt you to enter fresh
  credit card details.
• If the previous step did not work, don't waste time on online research or forums as this is a billing/account related issue. Straight away, head over to gethelp.live.com, start a chat with a billing person and they will take care of this.
  

 

Edit the credit card number on my account

My suggestion is to delete current credit card number. Then add new credit card number.

 

credit card details already exist

i have a nokia lumia 800 phone and i have also set up my microsoft account with credit card details etc.
when i enter the market place on my phone to purchase an app the phone suggests that credit card details are required and it transfers me to microsoft and when i log in and enter the credit card details , i cant get any further regarding buying the app
as a message saying credit card details already exist is as near as i can get to buying that particular app.
i have tried turning on and off my phone and clearing the web browser history etc and still when i try and buy a new app i get the same message that the card details already exist ?
any ideas on how to resolve this issue ?