Anyone had this issue before? Before when someone posts or PMs me, I would get the notification instantly but now it no longer does that. I tried disabling it and re-enabling push notification in settings, closing and re-opening browser, and even restarting computer but to no avail. Can anyone assist?

I have the same issue. Sometimes it works only when I refresh yhe page.

This happens to me as well but it usually ends up fixing itself. Sometimes I get push notifications before I get the JSP one if I'm active on site.

Try clearning your cookies/cache, re-enable everything, and reduce the amount of tabs open.