What are the reasons for a lot of water under the car floor mat?

[Meredith]

The reasons for a lot of water under the car floor mat are: 1. The sunroof is not tightly sealed, allowing water to leak from the sunroof to under the car floor mat; 2. Water from car washing was not cleaned up properly; 3. Rusting of the interior heater, causing water to leak under the car floor mat; 4. Aging of the car's sealing strips. The solutions for a lot of water under the car floor mat are: 1. Remove the car floor mat and clean up the remaining water inside the car; 2. Open the car doors to air and dry; 3. Adjust the vehicle's circulation switch to internal circulation to drain vapor through the air conditioning system; 4. Replace the car floor mat with one that has waterproof performance; 5. Check if the sunroof's drainage pipes are blocked.