Symbicort - The mouthpiece on my inhaler can be twisted around. Is the inhaler still effective?

There is only a small range of positions for the top mouthpiece where the drug is delivered, have made this mistake and seen the return of symptoms as turned inhaler off. Have contacted the manufacturer when this happened, but did not get a response, same problem for my partner and she is not getting the benefit of the medication.
With practice you can feel when the inhaler mouthpiece is out of position as when you suck for the medication, it feels as though the air flow is blocked slightly. Twist the top mouthpiece a few degrees and try again, repeat until you feel that there is not a blockage when you suck.
The ability to turn the mouthpiece & turn the inhaler off is a very bad design, guess it leaves many people with unnecessary symptoms