If you want help figuring out why things don't work then you need to provide better details than "common home router".
What I would do is find the exact manufacturer and model number, use google to find the user's manual, and then read the manual looking for the section(s) on configuring the WiFi access through the web UI. I would also look for a manufacturer supported user forum or the manufacturer's website and look for their support options.
My guess is that there is one check box (or dropdown) that needs to be changed to solve your issue, but finding that option with the information you have provided is impossible.