What do you have here? https://app.intercom.com/a/apps/_/settings/helpdesk/assignments

If you have it as “assign to me” and it doesn’t assign to you (assuming this is what you are asking, because you didn’t give much explanation), then it could simply be an Intercom bug (I’ve seen it not long ago). In that case, use your Intercom widget at the bottom-right to raise it to Intercom’s support and let them know. 

If that’s something else, please explain a bit more :)