Custom Coupons M2 - General Usage
Error Messages for each Rule
It is also possible to define different messages for specific cart price rule. For that, please go to go to Marketing → Cart Price Rules and select the rule that you want to modify.
Inside the edit rule menu, you’ll see the Custom Coupons Error Messages tab.
Under Manage Coupon Codes tab there will be a grid with additional statistics for every coupon error message.