Why cant I start the car in the Morning?

Hello,

You know the engine will warm up faster when the start driving as the higher engine speed will accelerate the warming process.
If you let the vehicle idle for longer than 10 minutes, does it warm up then?
Depending on the outside temperature it can take longer for the engine to warm up which can cause it to blow cool air longer.

https://www.2carpros.com/articles/how-a-car-heater-works

Another possibility is that you might have some type of restriction in the heater hose that only allow coolant flow when the engine speed is higher. This could be remedied by flushing the coolant and heater core.

https://www.2carpros.com/articles/coolant-flush-and-refill-all-cars

Please let me know of any questions.
Thank you.