AEM 6 - Get List of Tags

I'm trying to get a list of tags available but I keep ending up with an Array of 0

Example code:

        private List<String> tagsList = new ArrayList<String>();

        try{
            ResourceResolver resourceResolver = getRequest().getResourceResolver();
            // Session session = resourceResolver.adaptTo(Session.class);
            TagManager tagManager = resourceResolver.adaptTo(TagManager.class);
            Resource resource = resourceResolver.getResource("/etc/tags/bmi");
            Tag[] pageTags = tagManager.getTags(resource);
 
            for(Tag tag : pageTags){
                tagsList.add(tag.getTitle());
            }
        } catch(Exception e) {
            LOG.error("Error getting tags",e);
            throw new ServletException(e);
        }

All the tags live under /etc/tags/bmi.  I'm not sure why I'm not seeing an Array of Tags being returned.

Any help is greatly appreciated.

Thanks,

-Dean