I have a RazorCart site that has a bit of custom code and I'm having trouble showing an error message in some of the code. Setting the ActionEndResult to false and passing the desired error text in FailureMessage. But this doesn't seem to be working for me in code for the Calc and Checkout pipelines, specifically in our overridden CalculateSubtotal.
Is there a different way to surface an error message there? Or should the above method work?
Thank you,
G