Remove Coupon Code from input if coupon is invalid

The issue I am finding is that when a coupon is invalid, such as in my case when the order is less than £20 OR the coupon code is wrong. It creates a warning message saying the coupon code is invalid but the code is still remaining in the input.

This means that the user needs to manually remove the code before they can continue to the next step, and if they do try to continue to the next step, a new message appears at the top of the form stating:

'There are errors on the page. Please correct them and resubmit the form.'

This is not very user friendly IMO, would this be an easy fix?

Could we create a Coupon Rule Action which does this very thing, it removes the code from the input.