Profile: waldemarW

Problem:
Waldermar want to trigger his custom PHP function after the user is created by CRED form

Solution:
f you only need to trigger the action you mentioned above after the CRED form submitted, I suggest you try CRED action hook: cred_save_data

Also you can use WordPress build-in action hook user_register, which will be triggered in most cases(including CRED new user form), see document:
https://codex.wordpress.org/Plugin_API/Action_Reference/user_register
with the parameter $user_id, you can get the user_name of new user, function get_userdata()
$user_info = get_userdata(1);
$username = $user_info->user_login;

Relevant Documentation:
https://codex.wordpress.org/Function_Reference/get_userdata
https://toolset.com/documentation/user-guides/cred-api/#csd