I'm not a heating and cooling expert but I have and Idea, only because it happened to me last year.
I had the same problem, I called a service and was waiting for them.... they said they were busy until the next day..... this was 10 o'clock at night.
So I went downstairs to look at the furnace again, I made sure the dog didn't hit the switch, I checked the fuse, I even checked the filter. I don't know why I checked the filter but I'm glad I did because as I bent don't to pull it out I push against the furnace cover and it went on and them off.
The safety switch on the furnace cover was not engaging because the door was off just a hair. so I took the cover off, bent the rim a little, put it back on and the furnace has been fine ever since.
I hope your problem is that simple
Check it out
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