xjoint really stuck

Hey guys. I have had my xpole a little less than a month now and I put it up or tried to put it up today for the second time and my xjoint is mad stuck and appears the hex key may be stripped? I always completely insert the hex key and i thought the first time I put it together that the xjoint was very very hard to screw and unscrew it takes all my strength. Has anyone had this problem or know how to fix it. Please help it took me almost a year to save up for this one I cannot afford for it to be really broken!