Redeeming a voucher for a Nokia Music+ subscription will not extend your current subscription, but simply add itself on top and run in parallel. It is therefore not advisable to redeem a voucher for NM+ while you have an active subscription. Instead, cancel your subscription and wait until your current month run out before redeeming your voucher.
This topic is valid for:
Nokia Lumia 900,Nokia Lumia 800,Nokia Lumia 710