Reg PhonePe gift voucher validity

I bought some PhonePe gift vouchers last month from iMobile app using the 3% discount offer.

I know there is a validity of 1 year from the date of purchase.
But does this validity applicable only till we add the voucher in the app? I mean after adding the voucher in the app, can it be used forever without any validity restriction or it will still get expired if unused for more than 1 year?

Have the same doubt for Bajaj gv as well.