The most common problem is the aluminum shift tube in the steering coulumn breaks.
There also is 2 torx headed bolts that hold the shift lever at the base of the column that come loose or fall out.
You can check this by watching the base of the column where the cable is hooked up. Wiggle the shift lever, and watch to see if the cable moves at the same time as the lever.
If the bolts are loose, tighten them and try again.
If they do not move in unison,and the bolts are tight. The shift tube is broken in the column. It is also common for the bushings the tube rides on to be bad.
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