As the manufacturer also suggests, I would strongly recommend that you keep it indoors when not in use if at all possible. With an analog smoker I wouldn't be as concerned, but the digital or wifi units have sensitive electronics externally mounted which are not designed to be weatherproof. Even if covered you have temperature and humidity swings along with condensation that can occur and over time can cause superficial issues like in your case, or worst case brick the electronics completely.
To try to answer your question though, if it's possible to flatten out the faceplate flush by pushing on it you might try a small amount of super glue or epoxy along the seams where it's lifting off and put pressure on it until it sets. I wouldn't expect this to be more than a temporary fix though if you continue to store outside, as over time the daily expansion/contraction cycles due to temperature as well humidity getting inside will continue to wear at the unit. You could also contact Smokin-It and ask them since you've only had it two months and maybe they can do something for you, but I suspect they may tell you the same thing I did unless they are in a generous mood.
