If you mean the actual berries on your strawberry plants are going mouldy I'm not aware of anything you can treat them with to prevent this. Given the wet summer we are having it isn't really surprising, have you tried removing some of the leaves to get more air and light to the berries?

Do you have straw or something underneath to keep the fruit off the ground? Ours had mould last year & were not that brill, but this year we put straw underneath to stop them getting too wet & we have had some beauties so far this year. Could be that that helps. My gardening method is a lot of trial & error so I couldn't be certain!! I don't know what you could spray on them, because I don't like to spray anything that I am going to eat, but I daresay there is something on the market. The season is so short for strawbs isn't it, so it is disheartening if they get spoilt.
I see your ID is similar to mine!!

Where is the mold growing and are the Strawberries intact?

A tip I tried last year is the trench Strawberries, planting them at the top of the mound. The trench allows water to soak into the roots and the Strawberries do not touch the ground as they are raised. I found that the plants need lots of watering to get settled at first and for the roots to go down deep but afterwards works well and need little care. The air gets around the plant stopping molds.