There is a pin in there somewhere that sheared off most likely.
Call the company and see if they have them plus instructions.
You can get one of these based on the exact model for $100 to $200 so might be better to pitch it.
Simple replacement , 3 bolts, 1 wire connection.
2017 SLX 195RB
2021 Jeep Grand Cherokee Summit L 5.7L V8
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Prev. '14 Jeep Grand Cherokee Overland, gas 3.6 V6