Airtel — bill dated 13.05.2018

Address:

600102

I have been notified that there is an outstanding of rs. 1720.07 due on 21.05.2018, against my bill dated 03.05.2018 for my mobile no.[protected].
My current plan is infinity family plan - rs.799 with 9 packs effective 16.04.2018.
Now i received a bill dated 13.05.2018 for the period 02.04.18 to 01.05.18. For rs. 1720.07 due on 21.05.2018.
1. Please clarify whether i am still billed for my old plan.
2. Kindly mail details of my bill dated 13.05.18 for rs. 1720.07.
3. Also, notify my billing cycle for my present plan