1999 crysler van

my car leak into the front passenger side from under dashboard after rain and use of air conditioner

More than likely, the drain line from the evaporator box is clogged or disconnected. The moisture is backing up in the box and dripping into the cabin. You can blow out the line with compressed air.

You can blow out the line with compressed air. Or use some string trimmer line. In either case be careful. You can damage parts or blow the drain hose off somewhere that will be really difficult to put back on. ?