Blocked sunroof drains on a 03 renault megane scenic rx4 sport alize?

I've not had my car for very long but I have had a lot of water in my drivers side foot well. I've tested the sunroof drains by pouring a little water down them, the passengers one has a little come out but the drivers side one doesn't have any part from dripping down the side of the dashboard into the car. I've tried putting a washing line wire down as I heard this worked but it got stuck and wouldn't go any further. I don't know where the drains end up or what to do as none of the garages where I live say that they do sunroofs. I don't know anything about cars so I don't fully understand where things are. How do I fix it, what should I use or can I just seal up both my sunroofs with sealant and be done with it?