Please don’t do another hard reset (factory reset), it rarely helps, and erases any information that might help Sonos help you.

I’d suggest wiring that one Sonos One to your router with an Ethernet cable, and wait a minute or two. That will set up a SonosNet connection that the speakers can connect to. Using the controller, add both the ‘missing’ speakers to your system. Once all three are showing up, you can go in to network settings in the controller, and ‘tell’ all three devices about your network name and password. Then, if you want, you should be able to remove the network cable. If you want to leave one device wired, there’s no need to tell ahe Sonos about your network name and password, they’ll communicate through that one One. 

Thank You Bruce. I really appreciate the reply.  I tried the hardwire approach and it pops up as a new wifi connection.  Then when I select it, it tells me there is no connection.

Whenever I unplug the speaker and plug it back in and its flashing green, I select add product, My sonos one pops up, then it says unable to connect.

Im so sorry that i got rid of all of my old school audio equipment.

I appreciate your help my man.

Then I’d recommend that you call back to Sonos Support directly to discuss it. You might get someone who can help you better than your last person. 

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your Sonos system and network.