My chair arrived and I finished assembling it. I think there is a problem with the lever on the right side? It doesn't seem to do anything. I can't make it budge at all, and the chair back doesn't seem to stay in one place either. If i lean back it will go as far as I like, but if i sit foward it will return to 90*. I sent an email to support at Arozzi but i'm wondering if anyone else can help me here?