How can this warning message (AP-810197) be changed to an error?

Summary:

How can this warning message (AP-810197) be changed to an error to stop the user from creating the invoice?

I tried from the Manage Messages setup by changing the type from warning to error but it didn't work.

Content (please ensure you mask any confidential information):

Warning: Completing this match will result in an overbill. (AP-810197)

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Code Snippet (add any code snippets that support your topic, if applicable):