S430 Rear suspension Odd symptoms

[Bzoo]

I have a 2002 S430 which today while driving lost pressure in the right rear air strut. I restarted the car, the strut inflated normally and drove it home. By the time I reached my driveway, approx. 4 miles, the strut had lost it's air charge. I restarted the car, the suspension inflated to normal height, I put it in the guarage and it is holding pressure normally.
Any input would be appreciated.
Thanks for reading
Brian