A/C blows hot

I troubleshooted and the condenser comes on and the fan as well. It blows cold then I hear a change in sound and it switches to heat although I did not touch any dials. It also will not blow outside cool air. I think it may be a blend door issue but I do not hear any noises like the videos all suggest I should. The air direction does switch when I choose face or legs or defrost but air remains hot even with A/C button on. I check fuses they are good.
I had an auto part store check pressure and they did add some Freon which I do not think was even the issue. I found the blend door but it appears there are two. I am not sure why and I cannot find any diagrams for my car specifically. Is it possible one blend door is for direction of flow and the other is for cold/hot flow? I can get to the blend door and change it but before I try I thought I should ask your opinion.
Thanks for any help.