Your problems could lie in any one or all of a number of areas.

Mechanical - is everything tight that should be tight? motor couplings especially.
Electrical - are all connections sound?
Software - are your settings correct? Have you calibrated the machine?

We don't have a crystal ball on the forum and you will need to post more information about your software and settings. And Pics, lots of pics (preferably in focus).

Then we will do our thing and get you cutting properly.

Cheers,

Rob