Can you please clarify, as terms you’re using have certain meanings in a Sonos environment. 
 

When you say the One SL won’t pair, do you mean it can’t form a stereo pair with a second One? Or that you can’t connect it to your wifi, or that you can’t see it in the app? 

Have you deleted the old wifi credentials from the One SL? 
 

Have you tried leaving the One SL wired, powering off all your Sonos devices, then powering off and restarting your router? Make sure router is fully restarted and wifi running before powering up your Sonos devices one at a time starting with Playbar.

When you refer to “create a surround” you again need two Ones for surrounds. And the Wireless setting for your Playbar must be Enabled (and for the One’s as well). 

Hello. 
Apologies I can’t get the SL to connect to the internet via wifi. I can only connect it to the router with the Ethernet cable. I can see it in the app but asks me to fix it. When I do it says it can’t connect to the wifi. I can see it on my Vodafone app but has no ip address.  
I have no issue with my other Sonos One after I have restored it to factory settings and connected to wifi. IF go to create set up surrounds, when all are connected, the play one will not work and I have to reconnect it and it wont let me until I erase the SL to factory settings then it will allow me to connect the one. Then wire in the SL and I can play all.

I have reset all to factory settings and deleted the system reset the app and started again but still happens. The playbar is set to wireless and I have powered all down as you have described. 

Although underneath the speakers one says play one and one says SL can they be used together to create a surround sound set up and do they both have to wireless?

when you say removing wifi Credentials doesn’t factory settings do that?

Many thanks

Let’s start with a basic question, since there is no “play one”. Is it a One or a Play:1? Is the other a One SL? 
 

A Play:1 cannot be stereo-paired with a One or a One SL. 

Then can you confirm whether you have disabled the wireless on your troublesome speaker? Is the troublesome speaker the One SL?

Although they are both Play Sl in the App underneath one say play one and the other SL. 
wireless. The SL has not been disabled but after restarting as you stated one by one, stating with the playbar I attempted to add to the lounge as a surround sound and it’s now paired up after the second time.  Im unsure if I have a Sonos issue or Vodafone issue.

The speakers are off line in the Vodafone app

But online in the Sonos app and im currently using the surround in the lounge as we speak 

Sorry the SL is the troubled speaker I can’t add to the wifi

Visually Underneath each speaker, one of them says one and the other says Sl one. But in the Sonos App it states they are both Sl ones.

 My Vodafone app shows nothing online with the speakers yet in my Sonos app it shows full functionality and they are working.

I’m just trying to figure if it’s a network issue or a Sonos issue and giving as much information as I have to hand.

As previously mentioned the SL will not connect to the Wifi. I presume the surround issue will rectify accordingly once the wifi side is sorted. 

I appreciate your assistance though, and any further assistance I can get.

Hi @Ryan CT 

Welcome to the Sonos Community!

I recommend you get in touch with our technical support team, who have tools at their disposal that will allow them to give you advice specific to your Sonos system and what it reports and to find out exactly what’s going on with your Sonos system, though it does sound like you may have a faulty unit.

I hope this helps.

Had the same problem with the Vodafone Pro 2 router.

Could set up all Sonos individually, but when setting the Sonos 1’s as surround to beam, they would not pair together.

Sonos tech team were not able to help, the same factory reset/Hard wire advice. 

I think its more to do with how IP’s are allocated etc..