Hathway — Non refunding and non termination of Hathway ISP

I have already submitted the device to Hathway company staff 2 months back and got my account terminated, but inspite of it, I am getting calls from hathway side that i need to pay an amount of Rs 425/- for not returning the device and compelled me for paying the same amount if not customer care executive threatened me that hathway company will send a legal notice of cost Rs 3000 which is to beared by me.
In that case, I rushed to hathway company building which is located at Stanza building, Himaythnagar. Upon my visit I found out that there is no customer care section and grievences are noted by security guard and sent into the office. After a while person addressed my issue and said he raised ticket with service id 04032021w269539 on 04.03.2021 which will result in refund of paid amount Rs 425/- but upon checking in your website pack name:Fiber hd5 hyd 50 Mbps Monthlyu was found to be active with my account
Please do the needful at the earliest for refund of amount and acknowledgement of termination of my hathway account [protected].