To change the Shop currency of your in-game account (only for a valid reason such as yours – which should be approved), you will need to contact the Tech Support via this form to get it changed — providing all of the required relevant information.

What was the reason for the account block?

Gib tea

Unless both of you are from the same household (i.e. having the same IP address), it's considered account sharing and forbidden as per the game rules.