01 325i Climate Control Air Path not switching

Hi. My mom has a 01 325i that I can't seem to get the climate control to work correctly. For starters the climate control unit seems to be in working condition. I hear the blower turn on but I can't get it to blow air in either vents. Both the heater and AC work because at high speeds I can barely feel the air come through the vents. I switch vents but I don't hear the mechanism initiate the change (as I do in my 01 330i) Could it be a fuse? Something is stuck? Broken? Don't know where to begin on this? Any help? Sorry for the noob wording. Thanks