Front blower motor works intermittently

Hello, I am Danny.

It sounds like you are having an issue with either the blower motor relays(2) or the blower motor resistors(2). I have attached a few pictures of what they look like and a tutorial on how to test a relay. If you want to test these yourself I can send you a few test diagrams. Hope this helps and let me know if you have any further questions.
Danny-

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit