Voltas — unethical service by the technician

Respected sir/madam
With due respect i hereby state that i purchased an ac in the year 2016. This year in the month of march before lockdown i registered my complaint regarding the ac. My complaint was considered today dated 19.6.2020 in which the concerned person said that he ll be changing the compressor and ll fill the gas which ll be chargeable. First of all due to the lockdown period the customer must be provided extra 1 month as the complaint was considered very late. Moreover, the service should be free of cost. Next, the person who came to check the ac told us that he ll change the compressor free of cost to which we give the affirmation but on saying that we ll get the gas filled ourselves. He refused to change the compressor. According to me this is unethical. Kindly consider my complaint and provide me the best of your service which you promise to give while purchasing the thing of your company.
Following is the product number as well
As the place where the product was purchased.
Voltas ac 0.757 102 dya (4011199a16b001871) purchased from
Rosey electronics vikas puri
Regards