What else can I use instead of htp.print and dbms_output on toad for oracle PL / SQL?

Question

Currently I have htp.print and DBMS_output to show me the final result of user input. however htp.print shows the acknowledged message in a web browser, and my DBMS_output for some reason does not work. But what I'm looking for is a confirmation message that will appear and show the user. I tried java script and for some reason does not work. The following is the syntax.

- button and text input field

HTP.FORMOPEN ('BANINST1.UAP.P_UNSUSPEND_SEARCH', 'post');
    HTP.P ('<input type="text" method="post" name="bannerid" id="bannerid" placeholder="e.g. 000123456" maxlength="9" 
            autocomplete="off" required>');
 HTP.FORMSUBMIT ('', 'Submit', cattributes => 'onclick="confirmMsg()"');
    HTP.FORMCLOSE;

- javascript confirmation message that doesn't work

htp.p ('<script type="text/javascript">
                        function confirmMsg() {
                                var field1 = document.getElementById("bannerid").value;
                                alert(field1+" has been unsuspended");
                                }   
                   </script>');