How to clean the nozzle?
Sometimes the filament stucks at the feeder motor because the pulling speed is not fast enough when you unload the filament. Here is the solution:
1 Heat the nozzle to 260, make the residual filament in the nozzle automatically flow out.

If the nozzle is still blocked, please take it off with the wrench when it cools down.

Caution: Please DO NOT remove the nozzle frequently, because it will reduce the lifetime of PEEK
 
2 To clean the nozzle, you will need three tools: a needle, a tweezer, a drill.

3 Use the needle and drill to clean the nozzle.
Then reinstall the nozzle.

Not sure where you got this information but it will lead to a damaged unusable nozzle. The hole in a nozzle is not just a straight drilled out hole. It has a bevel on the inside and a bevel on outside and some times is even a bit higher than the nozzle rim. It has a very specific shape to control the filament flow. A drill can damage this shape and cause the flow of filament to come out wrong and cause printing problems that will be hard to diagnose.

As long as you are printing ABS just take the hot end apart and soak it in acetone for 12 to 24 hours and you can remove it with tweezers and smooth wire.

If the nozzle is still blocked, please take it off with the wrench when it cools down.

Caution: Please DO NOT remove the nozzle frequently, because it will reduce the lifetime of PEEK
 
2 To clean the nozzle, you will need three tools: a needle, a tweezer, a drill.

3 Use the needle and drill to clean the nozzle.
Then reinstall the nozzle.