That means not mixing corporate Gmail (or Outlook, or anything else really) with your personal email.
Not using the email for your AWS account to purchase home goods on Amazons retail site.
At best your have the mild convenience of a single inbox. At worst Amazon shuts down your AWS account because you open a dispute for a fake Beanie Baby purchased off the retail site.
(not very) funnily enough, we have a business AWS account that is also used for Amazon (buying stuff for the office), as well as Amazon seller central. We've set up MFA on the AWS account, but it's in total conflict with the seller central account, which keeps asking for setting up MFA as well. If we set both, we're almost totally locked-out of our AWS. Somehow the MFA device gets mixed up or something. We can kinda squeeze-in if we try a few times with alternating between codes. Seller central seems connected to the Amazon retail, but not AWS. Totally bizarre.
We've contacted AWS MFA support several times, but there's basically no solution for this. They claim it's all somehow integrated, but something isn't quite well integrated as it should be.
My guess is that you might be the only person/company who has this specific setup, so there's either no ticket, or it has a priority of -99999.
Still probably worth headscratching about internally...
(If emailing works out, I'd be very interested to know!)
But opening a dispute? Is this true?
Which is also not an issue if you use a decent email client. Even Win10 default Mail app supports unified inbox for multiple accounts.