I can not get a steady temperature

A question of a fellow grower: My room is 8x10 I have 2 -2000 watt LED’s. An a/c window unit and a 660 cdl exhaust fan and I can not get a steady temp to save my life it’s either 69 or its 85
Any advice would be appreciated
My room has fiberglass insulation in the walls covered with 2” insulation board

Are you getting temp swings when lights turn on ?
Youll always have a higher temp when lights on die to heat generation off the lights
I generally run 10 degrees warmer when lights are on

A 2 stage thermostat will help you to maintain good workable temps. Set the thermostat temp for your lights on period and it will control your aircon and at lights off your heating. the thermostat will keep the differential between lights on and lights off minimal. It will also help to maintain your humidity.