The twigs and branches may be too thick. Check that both levers are gripped firmly (if it has a double lever handle). The machine is a trimmer, not a cutter. Do not use it to cut thick branches.

We would not recommend that you repair it yourself, as it needs to be wired inside the machine. If done incorrectly, it could result in damage to the machine and as this is not covered under the warranty, repairs at an agent would be chargeable and it is not always cost effective to do this.