Kent - Kent Service

Hi All, Purchased Kent water purifier and it was working good. In the month of april ** got call from Kent service man to do general service. I allowed to do service and said filter kit expired and need to replace which was costed *.*k. + Service charge.He assured it will be * year guarantee/warantee for filter Kit and filter fiber one is * month waranty. . Only next year april **** need to replace. I allowed to replace it. I paid amount. But, bill not given to me. He said you will get online or you can login to http://www.draquaa.in/invoice/. When I checked that time it, bill was not generated. Again I got call from Kent and asked pending general service on *rd November **** . I thought just general services. I allowed to check. The person said, filter kit expired and need to replace it. I got confused and informed it was replace just april how it got expired.The fiber filter have only * months waranty. I checked the bill by login into website http://www.draquaa.in/invoice/. In the bill nothing specified about waranty. Now, I spoken with cm care, they also telling * months waranty for filter kit. The kent is fooling every middle class people by sending service person for general and charging big amount of money.