Hello,
When the class says it exists, it passes several verification checks.
The email server of a given email address will accept the message, but if the user deleted his account, any message you send to that address would bounce after some time, maybe a few days. It depends on what the server is configured to do.
I suggested sending a message to the email address you want to check to test if the address exists.
This is just the way email servers work. We do not control email servers. What we can do is explain to you how it works in practice.
Read this article to understand better the validation methods:
phpclasses.org/blog/package/13/post
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