Your mobile device needs to be connected to an 802.11 b/g/n compatible WiFi network (use WPA2 Personal security mode) and ensure the mobile controller device meets the system requurements shown in this Support link:

https://support.sonos.com/s/article/4875

You may also want to try setting up the speakers with one of them wired direct to the router.

@Brd4fun,

Also perhaps be aware that If a Sonos product has previously been setup on a Sonos S2 Household/System, then you may also need to downgrade the device to begin with, by following the instructions in this Support document (link below), but note also, to go onto create a brand new S1 Sonos Household, you must first use an S1 only compatible device to create the Household, you cannot use a device that is both S1/S2 compatible to create a new S1 system.

Downgrading a compatible S2 product to S1:

https://support.sonos.com/s/article/5097

Perhaps not relevant here, but also just FYI - A Sonos One-SL speaker cannot be downgraded to an S1 HH once it has been added to an S2 System.

Downgrading is a bit of a faf imho, you need to install S2 to do it.

Put a Sonos One back to S1 last week and was a bit long winded..