Carrier AC — Worst customer care service

I had purchased carrier AC last march and due to covid, I had installed in September. Since then I have been raising request for the ac service. Either the request is cancelled or the technicians never call. If a particular date is given, the technician calls and says he can’t attend it and cancel it. Is this the way you avoid doing the free service within an year and come for only paid services!? Then why the hell you have a customer care or warranty period!??? We can buy the ac and do a service from a third party! I patiently waited that things will get better as i also consider and understand the pandemic situation . But again if the service is not done, what about the expenses will I have to bear later . !!! Either serve for the customer or never have a service!