This sounds like a bad mode or distribution door actuator. The blend door would be the one that selects the temperature of the air and you say it works properly.
To get to the mode actuator the service information says you need to remove or drop the steering column as the actuator is tucked into a pocket in the dash next to the area the steering column mounts. To do so you need to first remove the trim around the column. Then you will have an open area next to the column, at this point I would look over the way the actuator mounts and see if you can slip a hand and some small tools into the area to remove the actuator in an attempt to lower the amount of work needed.
This post covers the same issues as well as the temperature door:
https://www.2carpros.com/questions/passenger-side-blend-door-actuator-location
The hardest part on column removal is that Ford hid the airbag connector above the column, works okay when they are building the car as the dash goes in after the column, not so good if you need to work on them after that as you need to use a mirror and angled pliers to reach them.
Then you remove the other wiring and then remove the column bolts, these are one time use bolts so you need to get the replacements from the dealer prior to removal.
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Sunday, June 13th, 2021 AT 11:20 PM