I'm trying to send an email by extension Mageplaza Smtp and when I config, and send mail, at first, when i enter Username and Password and click "Test now" in "Send test email" section, it sends email successfully as expected.
But then, I click "save config", and then the page reloaded. After that, i click "Test now" and the page show an error message says "Username and Password not accepted".
May i do something wrong?
Here are my config, please take a look:
Also here is default Magento config, I've change Enable to "No".