Air conditioning stoped working

Hi I have a 2020 Kona with 20000 km on it ,the air conditioner stoped working no heat or cold fan still works, I have it book in a the dealership for repair next week.
This morning when I tried to start the car I got EV warning light came up and message to check electric system and would not allow me to select drive or reverse, I checked the battery in the engine bay it was 14 volts I tried to start it several times still getting same EV warning light and message. I disconnected the negative battery lead for 20 seconds an reconnect it, when I tried to start it the warning light and message are gone and everything except the aircon is working.
I was wondering if any other owners have had similar problems.
Cheers Tony