Airtel — Airtel xstream broadband and Dth payment term problem

Hi sir,
I've taken 6 months of Airtel Xtream fiber with the price of 4000/- on 3Rd Nov 2022.Made payment on the link provided by Airtel representative. The payment was success from my side. xtream purchased through sales manager
(G.SUDIN
AIRTEL sales manager
AIRTEL. BROADBAND
Mobile: [protected])

And representative
(Bharath
[protected])

They gave 6 month combo offer, and Amazon and Disney hotstar 3month free, That's why am changing my existing tata sky dth and local broadband if any tariff different mean i continued as on same network. recently i got mail from Airtel to pay bill …I was purchased with 6 month combo…how it would come within 3 month itself.., then i spoke customer care and sales manager, they said 3 months only paid 2600 from customer care, and sales manager said 4.5 months tariff given, if 4.5 month tariff mean is just per month 826 rs without offer whoever get this 4000 bulk payment, .I don't understand

amount which I paid u has validity of still 1.5month more….how your are calculating? Y I should pay again and again….Airtel is a big network I didn’t expect this from them…kindly give a proper response for my amount which I paid Rs.4, 000

here i attached Airtel broadband no and bill copy and recently received 4.5 month tariff slip, and mode of payment acknowledgement.
my main problem that time your representative don't gave any acknowledgement,

From your side they asked me to pay the bill before 28th….so kindly solve this issues as soon as possible

Thanking you
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