Moisture in the Smart City Coupe

Hello! I hope you can help me! I’ve been driving a Smart City Coupe for six months and have been having a problem finding moisture in both footrooms for several weeks. On both sides the carpet underside is dripping wet! Have dried the carpet several times and after a ride in the rain it is wet again. What can this be? My car dealer has already renewed both door rubbers, resealed both rear window windows and examined the entire car without Erfo lg! Maybe you can give me some useful tips. Thank you!!!