It sounds like the common Bravo problem: broken plastic connector between flaps and the actuating motors.
Read the climate control faults use
MES/FES.
1. Print-screen of the current errors (save it so you can spot permanent and intermittent errors).
2. Clear errors.
4. activate different options on the climate control panel.. up,down, front, hot cold..
(this will cause the permanent errors to show up)
You should see something like "windscreen actuator signal out of range"..or "signal high/low".
It sounds like the common Bravo problem: broken plastic connector between flaps and the actuating motors.
Your flaps are stuck in between positions, that would cause low blower power as the airways are partly blocked.
The parts are cheap.. but fiat will not replace the motors unless they are completely dead.. that means that the old motor will continue to force the new plastic connector until it brakes again... but replacing the motors isn't the cheapest option.... best thing would be to unclip the motors and clean the potentiometer before replacing the connectors.
As for the work.. that is another story.. it's really hard to get to them ( on the Stilo it was easily accessible ..but on the bravo there is a big metallic thing in the way).
In order to get to them Fiat specifies it needs to remove the doors, the seats , the center console, the steering column, the dash, drain the freon, drain the antifreeze. remove the AC/heat and blower along with the metallic bar in the car that stops you getting to the motors.
So yeah expect a big bill.
I can also be done without removing the dash.. but it's a back braking work because the awkward position.. and takes hours.. and involves drilling through the metal so you can get tools in, to remove the screws ( 3 on each motor)
Here are a few pictures to get a better understanding of the problem:
View attachment 145738
View attachment 145739
View attachment 145740
View attachment 145741