Kitchen Large Electric Appliances - water in freezer door seal

I have a Zanussi fridge/freezer bought earlier this year. Recently, on opening the fridge door, I have noticed that there is water in the top freezer door seal, with black mould forming. The fridge floor is not wet, so water is not leaking form the fridge, and the freezer door seal is not broken. Possibly condensation - if so, is there any way to prevent it?

Check seal for proper fit and warping. Seal should be airtight. Make sure door is not warped. Adjust as needed. Close a dollar bill horizontally behind the seal, leaving a little sticking out. See if it can be easily pulled out. If it pulls out easily, the seal is not tight. Check to see if refrigerator is level. If not level, door and seal may not be properly aligned. Adjust legs accordingly.

Mold and mildew spores are everywhere in the air. When they find moist areas on which to settle, they settle in. When warm, humid air encounters cold surfaces, such as around leaky refrigerator and freezer seals, condensation forms. This condensation and the dust on the top of door seals provide the moisture and food needed. Eliminating moisture and the food source will minimize opportunities for mold and mildew. They will not grow on clean, dry surfaces. Mold and mildew can be 'killed' with bleach/water solution. When cleaning, pay particular attention to the 'grooves' in the seal. An old toothbrush may be helpful with cleaning. Regular cleaning of seal with antibacterial soap will keep mold and mildew at bay.