I invoiced a customer and they mailed me a check minus sales tax along with a note reminding me they are tax exempt. (We just switched to RMS and I failed to flag them as exempt when I created them in the system).
How should I handle this? Our old system was more basic and allowed me to open past invoices and edit them to fix things like this. I'm having a hard time transitioning into this new way where things are more set in stone. I wish I could edit their invoice and remove the tax but I have a hunch I can't. Do I need to void the invoice and make a new one? Or adjust their account? Or ... ?
I would be thankful if someone could give me advice.
Thanks.
--Ryan