can't access $input['username']

Hello, I am using Auto Actions plugin and CB onAfterUpdateUser trigger with "Condition: password field - Not Empty". When the trigger fires, I need to get username and password. Also I don't want users to be able to edit their username, so I set it to "read only" in "Field Management" and/or set it to "Username Edit - No" in "User Profile Configuration". After disabling username editing, I can no longer access username from $input.

$input With username edit ENABLED =
{"view:"saveuseredit","option":"com_comprofiler","Itemid":111,"task":"saveuseredit","id":"348","6f553b1ee9a370f5b813fad82b229602":"1","username":"aaaaaa","email":"zederis@gmail.com","password__current":"zzzzzzzz","password":"aaaaaaaa","jform":{"params":{"editor":"","timezone":"","language":"","colorScheme":""}},"canvas__choice":"","avatar__choice":""}

$input With username edit DISABLED =
{"view:"saveuseredit","option":"com_comprofiler","Itemid":111,"task":"saveuseredit","id":"348","6f553b1ee9a370f5b813fad82b229602":"1","email":"zederis@gmail.com","password__current":"aaaaaaaa","password":"zzzzzzzz","jform":{"params":{"editor":"","timezone":"","language":"","colorScheme":""}},"canvas__choice":"","avatar__choice":""}

Is there another way to access username using onAfterUpdateUser trigger in Auto Actions with username edit disabled? Or do I have to go another route?
 

If username edit is disabled then there won't be any input data for it as the input doesn't submit with the post data since it can't be edited.

Ideally you should just be using user substitutions. So for example [username] will always give you their raw database stored username regardless of that setting. Recommend taking a look at our substitution tutorial below.

www.joomlapolis.com/documentation/279-community-builder/tutorials/18353-using-substitutions-throughout-cb

During profile update, if their password was changed, you should get the plaintext password with [password]. If it hasn't changed you'll get an empty string.

Tahnk you

hmm... in Auto Actions Parameters, Substitutions are enabled, but I have no clue how to make it work. I am outputting string in text file using:
file_put_contents("xxxxxx.txt", PHP_EOL . [username], FILE_APPEND | LOCK_EX);
or
$usernm = [username];
file_put_contents("xxxxxx.txt", PHP_EOL . $usernm, FILE_APPEND | LOCK_EX);

but it doesn't work. It seems like all tutorials or explanations start in the middle and doesn't explain from the start.. for a newbie like me. I spend hours upon hours experimenting and trying to make things work and it is getting very frustrating...

Substitutions need to always be treated as strings. You're causing a PHP syntax error with your current code. Enable debug under parameters to see error output. So in your case change [username] to '[username]' and it should work fine.

Yes! That works. But...
I need to sync password to another database every time it is being changed. When the user updates their password in profile settings I can easily access clear text password through the substitutions. But I can't figure out how to access the password when it is changed to random generated one during Forgot login process.