Is the error that you refer to "The warning details were not filled as expected. Please try again."?
If so, then that error is displayed for exactly this reason.
There may be things we can do so that the button is disabled but that might complicate some other factors, such as when to re-enable the button in the event of an error, and so on, which could mean the form gets locked entirely which is less useful.
On the whole, I don't feel inclined for us to make changes here.