Multiple API Keys

I am setting up multiple wordpress sites for clients. Most of them freak out when they get an email about an api key, don’t know how to forward emails, and so on. I thought I had found the perfect solution by setting up an email specifically for api keys and using it for all the accounts. After two successful accounts of using this method, it is now telling me that email address is already in use!
So how does everyone else deal with getting api keys for clients who haven’t got a clue?
Any advice?
Is this a bug of sorts for the wordpress boom that is happening?

Schwabbyfw