That has happened to me before.
Like the others said. Moisture is the pellets worst enemy.
Make sure you clean out the burn pots and the hopper after ever use. If you leave pellets in your hopper they will start clumping.
And start trying new pellets and see which one work the best. I prefer BBQ Delight Pellets.
Good luck. Feel free to PM me with any other questions you may have.
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