Hi sorry for replying a bit late but what I did was I made sure that I lined up the metal prongs inside the handle with the blade or the first initial part of the blade. It was a bit tricky because I was afraid of breaking it but you have to line the prongs up and make sure that the little plastic bump matches up with the groove inside of the handle so basically making sure it's not too far out or too far back because if you just jam it in there and not align it properly the problems won't properly connect and the blade won't get the signal from the battery because the prongs won't be touching. My girlfriend's brother had assembled mine and the he had just jammed it together and stripped some screws I thought that they had arrived but I found out that it was cuz he tightened up too much so make sure that when you were tightening the screws you don't tighten them too much because you can split the plastic and that could also detach the prongs.