I would suggest you have a fault in the control system and the ECU is detecting it. Normally if it tries to run the pump and nothing happens or the levelling sensors disagree.
You need to get the code read to try and fing the fault but this could be the start of a very expensive, and common fault chasing program.
I would start considering some coilovers to rid yourself of the system as the complete kit will be cheaper than a single OEM airbag strut.

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Black E53 V8 on 20's, lowered, drilled discs and poly bushes, strut brace and adjustable sway bars.