Change the "unchecked-message" of a checkbox

I’m new to Webflow, so maybe this is easy so solve.

I started building an e-commerce and added an “additional info-container” in the check-out form. I changed this to a Terms and conditions agreement. I marked it as required, so you cannot place an order without checking it, but I want to change the message when unchecked to something like “You have to read and agree to the Terms and conditions”.

How to I do that?

Thanks

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