American Home Shield [AHS] review: Installation of heating/air conditioning unit

In June 7, 2023 we had our hvac system replaced thru ahs's upgrade program. It is now October 16, 2023 and we wanted to change the air-filter. Guess what? There isn't one. No filter, no rack to put it in. The company that installed the unit, Millinial hvac, just came out and said they would write up an estimate. Can you belive it. They didn't do it right the first time and want us to pay for their mistake. Absolutely not. Called ahs. Absolutely no help. First, you can't understand any of their agents. I have spoken to about 5 of them since Friday (it is now Monday) and they all have such a heavy accent and they don't speak up and there is noise in the background. A perfect storm to not be able to hear or understand. They are not helpful. You can't talk to a Manager or any type of Boss. Only the escalation specialist. Really poor service. I want to know what they are going to do to rectify this situation. What type of damage has been cause to our system by not having any type of filter for 4 months. I think a good faith effort for the poor execution of this project and the lack of trust we now have with/for ahs.