Aqua Ultra - Overcharged Rsfor RO Water Purifier Filter CTO Chlorine Taste Odour 10 Inch cartridge

Hi Consumer Forum Support Team,
‘Jai Hind’ & Greetings.
I want to register a complaint below with you as I am overcharged (Rs ***/-) for RO
(Water Purifier/ Filter) CTO (Chlorine, Taste & Ordour) ** Inch cartridge.
Details as below.
Bill-cum-Receipt & Vendor details:
Bill-cum-Receipt No: ***, Dated **-*-****, Amount: Rs ***/-
SMC Traders, RNC Road, Subasgram,
South ** Parganas, Greater Kolkata (WB) - ******.
Babai Das, Mobiles: ********** (VF), ********** (Idea), **********,
**********,
Email: dasbabai***@gmail.com,
Whereas later, I found this cartridge being sold at Rs **/- (PFB the link).
https://www.indiamart.com/proddetail/ro-carbon-filter-cartridge-
***********.html
IMPORTANT Points:
*) This Bill-cum-Receipt was provided to me on Whatsapp on Sunday, **th June ****
post constant follow up for * weeks (Since Sunday, **th June ****).
*) Babai Das was sent to my home by Aqua Ultra (Mayur Enterprises) Company (I
purchased this RO online from them) as he is their authorized Service Provider at
Kolkata (WB) catering with installation & service for all ROs sold online by them.
*) I was also charged Rs ***/- as installation charge by Babai Das for which he has not
provided any Receipt inspite of several followups since **th June ****.
*) I did requested for a hard copy Receipt while paying him through Paytm. But he
insisted to pay only in cash & said me to have trust/ believe him that he will provide
me Receipt for Rs ****/- paid to him in cash.
*) He has also not rectified the * leakages yet in the new RO installation done by
him. Though the same was informed to him immediately post the installation the
same day (**th June ****).
Thus I request your kindself to Pl support for getting this resolved.