Husqvarna chainsaw stops when using it

Check for spark by removing the spark plug and grounding it to the
metal part of the cylinder. It should spark a bluish, yellow strong spark when you pull the starter rope. Make sure the SPARK PLUG is good . Get a known good spark plug. By using a plug that you know is GOOD, it will eliminate any chance that you have a bad plug and that the ignition module is good too. If the known good plug is not sparking then you may have a bad ignition coil. For replacement of that one you will have to remove the entire left coil cover and the ignition coil is by the flywheel or under it.

Check for spark after it quits. If none, the ignition module may be dying when hot. If ok, check the muffler for plugging. Use compressed air to remove sawdust from cylinder and head area. If everything looks good, note whether the spark plug is getting wet with fuel after trying to restart the saw. If dry, check the fuel lines for cracking or other deterioration. Make sure the fuel tank vent is clear of debris. (Loosen the fuel cap for a moment, then see if it will start.) Hopefully, one of these suggestions will hit on the problem!