There is condensation inside the appliance or on the bottom of the vegetable drawer cover.
Did you store hot food without cooling it first?
Cool the hot food first before putting it inside the fridge or freezer.
Did you leave the appliance door open?
Although the condensation will disappear soon after you close the appliance door, you can wipe it with a dry cloth.
Do you open and close the appliance door too frequently?
Condensation can form due to the temperature difference from the outside. Wipe out the dampness with a dry cloth.
Did you put warm or moist food inside without sealing it in a container?
Store food in a covered or sealed container.