If you are an admin and you already created some bot account on your community, but sometimes your bot users are not available, please make sure you are using them in the correct way:
1. Try to refresh you page after you logged in as an admin
2. When you want to ask or answer a question using a bot account, make sure you pick the bot account first, and then start to type your text. Once you insert text to the question/answer box, the text will be assigned to your own account and will be save as a draft under your name. So, please make sure to choose the bot first and then start to insert text.