What to do with dirty dryer vent?

If you can pull out the lint trap, do so and make sure it is clean. Unplug the machine and pull it away from the wall. You should see a flexible vent that is attached both to the machine and to the wall. Disconnect it to be sure it is not plugged. If it is cracked, then you should replace it so that the air cleanly goes from the dryer and out of the house without leaving lint outside the dryer.