No heat

For me that has always indicated that my coolant level is too low. I just put a little water in every other day (at the radiator cap only when it is stone cold) or so until I can figure out where the water is leaking out. Of course have to add actual coolant too every now and then to keep the water coolant mix fairly close to right. The system has to pump coolant all the way to the passengers in the back too so lots of places for trapped air bubbles in that system. They are hard to get out and will cause lack of heating. Parking front up on a steep drive may help. Obviously, you need to find and fix the leak sooner than later.