Reliance Digital — New Voltas Ac not working even for one day

I have made a Purchase of New Voltas Ac on 7th april 2023 but they installed on 11th April 2023. They installed the ac and waited for only 2 minutes and informed that it is working.
After then when we tried to on the ac it is not working. On the next day we tried to approach and inform that the ac is not working then the reliance store people tried to escape by saying that we will send the maintenance team but no one responded after then. We waited and requested to change the ac. Actual complain should be registered on 13th April but they registered it on 17th April. After waiting long time when we went today i.e. on 26th April they are saying that replacement will takes place only within 7 days of invoice date but not on installation date..

Please help us on this issue.