VIP subscriptions purchased via Apple (iTunes) cannot be up, or downgraded from within the BlockStarPlanet app, or by BlockStarPlanet support, as these purchases are connected to your Apple ID.
If you do not have access to the Apple account, please contact Apple account support.
Note: You cannot have more than one active subscription per Apple ID. You cannot have multiple users with active VIP subscriptions purchased through one Apple ID - not even if the subscriptions have different durations.
If you wish to purchase a VIP subscription to more accounts, please contact support for further guidance.