MySQL connection error PHP

MySQL connection error PHP

This may seem redundant, but I browsed through many varieties of this
question and nothing really helps.
I have a domain www.test.co.za
I want to connect a MySQL database using php's mysql_connect method.
mysql_connect("test.co.za","test_user","u$er23");
when I run the query I get this error.
Warning: mysql_connect(): Access denied for user 'test_user'@'server'
(using password: YES) in PATH on line __
I called for support from the Web Host and I've not seen any changes
because they just put me on hold for long periods of time.
This is on a shared domain, and the user test_user was created, the
password is correct, the server name... I don't know if it is correct.
Please help me, I'm so frustrated. Thank you