get_body_params() is always empty in POST request

The value you’re trying to send in the body is not valid JSON:

{
    "userID" = 3
}

JSON looks like this:

{
    "userID": 3
}

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)