Ask HN: Google Apps email account being used for fraud

I have set up a business email account with Google Apps. I have had this account for a few years. Over that time I have received automated order confirmations from Grainger.com. The confirmations are for a business that doesn't seem to exist, the owner of the non-existent business shares my last name, and is not my relative. I have reported this likely fraud to Grainger, but it continues.

What can I do to make this stop? I don't want my domain to become linked with some fraudulent activity, and get booted from Google Apps.

Does anyone have any interest to help me get to the bottom of this conundrum?

Thanks in advance.