What If a Client Doesn't Have an Email Address?

A unique email address is required for every user.  This ensures that the session history is always valid and unique for that listener.  One way to set up a unique email for a client that doesn't have one is to create an alias email.  Most email providers have an option to create aliases.

There are several ways to create multiple email addresses in Gmail .

For instance, if your email address is hello@gmail.com, any email that’s addressed to either he.ll.o@gmail.com or hello+world@gmail.com will also be delivered to your main inbox since Gmail ignores dots and anything that’s after the plus symbol in email usernames.