We're sorry for the trouble this may have caused you — let's see what's going on.
A few questions: are you getting this message to all voice commands? When did it start happening? Were there any recent changes on your network or set up?
Make sure your Google Home Mini is within 15-20 feet of your router and connected to a private network. Try rebooting your Home Mini and router to refresh the connection. If the issue persists, try resetting your Home Mini to its default settings.
Thanks for posting. It looks like you have an existing open thread that has a similar message and I already replied to it. I'll merge this thread with the existing one. You may check it and continue the conversation there as this thread will be locked automatically once merged.