Data Migration error message, “Unable to connect. Old Mac could not be reached."

Trying to transfer information from my old mac to my new mac using the migration assistant and I keep getting an error message “Unable to connect”. “Old Mac could not be reached. I have done all the steps many times and still get stuck at the place where you hit continue to transfer the information, I keep getting the same error message “Unable to connect”. Both computers are on the same wireless network, etc. Ensure both macs are on and connected to same network. You may try temporarily turning off firewalls…. I turned off firewalls and both macs are turned on and connected to same network. I have followed migration assistant step by step to no avail….can someone please help?

Rlvj

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