If Ask a Question isn't working because the button is greyed out and won't open, try closing all of your Learn tabs in your browser, and reopening Learn in one tab. You may have had too many tabs open which can cause the tool to stop working.
If the tool appears to be working but no one is answering your question, it is most likely functioning properly. If you are in a community program which does not include Technical Coach or Instructor support, or the Technical Coaches are not on online, try answering another student's question and seeing if they can help you in return. Schedule a study group to review the material with a group of students. Try direct messaging a friend for help, or querying the community in Slack.