ERR ADDRESS UNREACHABLE

Hi, 
I bought a theme and installed it correct. after editing visuals contact form stopped working. Though its a bug from dev side, although after investigation they told me to contact you since the error must be from your side. 
It fails to load second step of three in form and error in console is folowing: 
Failed to load resource: net ::ERR_ADDRESS_UNREACHABLE

Help me out guys, thanks