Stuck on previous owner Network Login

I recently brought an OptiPlex 3080 SSF from Goodwill and restore it back to factory setting. One problem, as it is setting up the basic, everything is fine until I get to Network, the previous owner, a company, wants me to login as if I was employed by them. Not being an employee of the company, I have no knowledge of the login procedure. It will not let me do anything on the page without a login. I can't move forward or back on the page. It sits there waiting for a login. I used the recovery disk several times, getting the same problem with the login. Can someone please help me fix this problem. Thank you