Hindware Sanitaryware Collection [Hsil] — Concealed Cistern for Home - Continuous Service Issues

We have installed Hindware's Concealed Cistern for our Home (2 Units). Both of them are causing continuous issues of water leakage despite having their executives come over a number of times and they doing some repair and mentioning that it is resolved. But the issue is not getting resolved and the executives are coming and replacing one or the other parts and taking some money for the repair.

Its now getting to a level of just removing the product and replacing with some other one and i am hesitating because it involves breaking the wall and replacing everything totally.

My previous complaint tracking ID's are as follows and I am having the same issue again now -
CB022366 - February 2020 - Syamala Venkatesh - Amount taken is INR 1850 (19/2/2020). Issue came back in 2 months and we had to wait because of COVID.
DA000692 - January 2021 - Gummalapati Brahmam (This guy came twice for the same repair) - Amount taken INR 950 (5/1/2021) + INR 1600 (18/1/2021)
DJ004274 - October 2021 - Gummalapati Brahmam - Issue raised but technician not showed up and Customer care responded to get another plumber and not the technician.