I have found on more than One occasion unplugged sunroof drains. This requires the headliner to be lowered, the sunroof "Cassette" which is the body the Glass slides back and forth in has a Gutter and hose system. At each corner of the "Cassette" has a Rubber hose attached. Usually one of these hoses is Disconnected. Or the plastic portion where the hose attaches to is broken. the unions are cheap to replace as long as the "Cassette" is not broken. Hopefully you will be able to just plug the hose back on. But you will need to drop the headliner to figure this out.