Mould can be a difficult problem to deal with, especially when it comes to mattresses. If you think you might have a mould problem, there are a few things you can do to try and remove it. First, make sure that the area is well-ventilated. This will help to prevent the growth of mould. Next, clean the area with a mild detergent and water. You may also want to use a bleach solution to kill any mould spores that are present. Finally, dry the area thoroughly to prevent mould from returning. If you have tried these methods and the mould still won't go away, you may need to replace your mattress.