add tooltip jquery by id or class

Question

good afternoon guys, I'm doing some finishing touches on a legacy system, it is necessary to add classes in different divs to show tooltip, but in the system I can only assign a claase to all tooltips, not by id or class. For some reason the class is not added , a good part of the system uses php's include_once to add a page, I don't know if that would be it, because in a pure htlm file it worked in isolation.

uma das divs que quero adicionar class no tooltip

     $(document).ready(function() {
    **$('#id').tooltip({
        tooltipClass: "mytooltip",
         }); 
        }
        }**