Kent RO — UV failure/ Low minerals Error - Technicians rude behaviour and

It's been only 8 months and this is the second time I've to approach for faulty product. This time it's showing an error - UV failure/ Low minerals Error. The tech visited my place today is asking for changing the carbon filter and sediment filter without examining the machine. He's quoting that we didn't buy additional sediment filter from him and now every six months you end up paying 1000+.

The tech visited is asking for 1100/- for changing the parts which is not even a year old. Over and above this issue the technician visited is extremely rude and threatening us that if you'll not change it now, I'll not visit again and if any other guy come he'll destroy the machine but I'll not come and fix this.