That sounds upsetting. Don't lose the spirit!
If the transaction failed you can reuse the voucher starting with 7 post 30 minutes as it gets blocked for safety measure. In case it is a voucher starting with 8 voila! reuse it right away. Please stand by till the mentioned time. If the issue persist we're all ears to guide you.
In case, of Filmy pass coupon code you can re-use it post 20 mins.