Users are allowed to change quntity

Hi,

I am using your plugin to set the minimum quantity of a specific product to 15.

The theme i am using is Enfold.

The select box starts from 15 and by using the minus (-) sign users cannot go lower.

But if they put for example 10 in the box, they are allowed to checkout with a quantity less than 15.

URL: https://www.strovolos.org.cy/en/product/bags-dor-pruning/

How can i overcome this problem please?

Thank you

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