Rear Air Shocks stuck fully extended

About a week ago noticed the wife's van rear air shocks are fully extended and seem to be stuck in that position. Usally after sitting for a few days they would settle back down to a normal level position. Was wondering if there is any way to release some of the air out of the rear shocks by hand. If anyone has any suggestions?

Thanks in advance.

It sounds like the sensor for the level control is bad. If they settle out after a few days, you could pull the air compressor fuse or disconect the air compressor after it is level.