As a prefix for a service's username, are both "iam" and "its" acceptable?

Assume a username for a service, for example, this site.

If my name is Alice, but Alice is already a registered username, what would be more correct? "iamAlice" or "itsAlice"?

I think I have never seen the former in the wild, while I have seen a few using the latter variant. For example, a coworker uses "itsBob" both in Telegram and Twitter.

So, my question is rather, is "iam" acceptable in this context? Or should I assume the same rules as when speaking over the phone, that we usually say, "it's Alice" instead of "I'm Alice"?

Solution 1:

A friend of mine uses the "iam" prefix to her name, as a social media username.

Since it is a username, however, it doesn't matter which you use (or even something not related to your name), as long as it is not already in use or prohibited by the service's rules.