I looked at my FR301 and it looks exactly like yours - slightly out of alignment. Never noticed that before! Anyway, I stuck a screwdriver in there and gently moved it back to center. As you have experienced, I never had any problem with the functionality of the desolderer.
Normally I would suspect Amazon as a lot of things bought from them are counterfeit or damaged seconds or returns. But I bought my FR301 directly from an authorized dealer, so I guess it's not an Amazon "thing" in this case.