Another cause of random behaviour I have seen is caused by intermittent connections between the driver pack & the solenoids. The socket contacts inside the 12-way connector get expanded with age & hot-cold cycles, so the valve become intermittent. The ECU either reports valve stuck errors, or over-adjusts when the contacts are ok.

That said I tend to agree it's more likely height sensor issues, where the ECU thinks the car is not lowering, and keeps trying until it reaches the bump stops.

To avoid the long drives on the bumps when it happens, get a set of schrader valves & tyre pump for emergency get you home use.