Although it is not a common problem for the product to gather mould, it can happen if the item is not dried correctly and packed away indoors after every use. The item is made from Nylon, and as with all materials, if left wet, or left outdoors for a sustained period, this may occur.
We would recommend that the item is cleaned using a soft bristled brush and water only. Unfortunately, we would not recommend using any type of detergent on the material including mould remover. This could cause more damage to the material.