My neighbor used to have an wifi connection shared with some other neighbors few years ago. Then they stopped using it now my father and the same neighbor wish for a shared wifi connection again. But new connection will obviously cost something and theres that previous connection still lying around. Even a 5ghz router is still connected to the line. But the problem is they don't know who was the broadband provider back then as the other guys handled everything. I have reset the router and login but no help. What can i do?