Can’t reinstall MacOS

I have a 2010 iMac that was running High Sierra.

I erased the OS through disk utilities and now I am trying to reinstall.

i am connected to my WiFi and select ‘Reinstall new copy of macOS’ High Sierra. When I click continue about a minute later I get a message saying “ the recovery server cannot be contacted. “

what options do I have at recovering my OS??

HELLP! If you questions please ask!!