This means that your mac tried to start up over the internet from macOS recovery, but it couldn’t
Try this steps in order to fix this issue
- Make sure your Mac can connect to the internet. If you're not asked to choose a Wi-Fi network during the startup process, choose a network from the Wi-Fi menu , if available.
- Press Command-R at startup to try using the built-in Recovery system instead of internet Recovery.
- Connect to the internet using Ethernet instead of Wi-Fi, or vice versa.
- Connect to the internet from a different Wi-Fi or Ethernet network. Your network configuration may not allow the internet access that macOS Recovery needs.
- Try again later, because it may be a temporary issue.
- Start up from another disk or volume, if available, or use a bootable installer to reinstall macOS.
If you see a black screen or some other screen during the startup process, find out what to do if your Mac doesn't start up all the way.
If you still need help, contact Apple Support.