I suggest you first check for updates on the Ray and then try to add the Roam.

If that doesn’t solve it, factory reset the Roam and then add it to your system..  You will almost certainly need to update the Roam.

Do not reset the Ray under any circumstances..

When you took the Roam away you mentioned you added it to another network… can you clarify if you added that ‘other’ network SSID/credentials to your Roam (so that it is still listed in the App network settings)?…or did you ‘factory reset’ the Roam and delete the Home Household in the process? - There are different ways to setup a Sonos product to work on a different network - see attached screen recording showing the steps of adding a new network via the App to a Roam where it is then able to operate on a different WiFi network. Note the attached is just as an example showing the start of the process required.

Perhaps post back the steps you took when away from your Home setup.

I have completed both tasks you mention and still nothing. 

For some reason it is now classing my Ray & Sub as two different S1 profiles and it seems there is noway or combing the Roam to this profile. For some reason even when I search it on the wifi on the sonos app the roam doesnt even highlight. 

All seems so strange when its been perfectly working fine. Also seems stranger that it connects via airplay on the spotify app 

When I go on to the System settings and check App info, 

It doesn’t even label the roam, yet I can go onto the wifi settings and update as a product, plus I can still connect to other apps as mentioned @Ken_Griffiths @John B 

Sounds like you created new system rather than adding to existing. Try another factory reset. Then be sure to add it to your existing system. 
 

Edited to add: I shouldn’t assume, so please clarify. I think Ray and Roam need S2, not S1? 

Would you recommend factory reseting everything?

As I am certain I have factory reset the roam 2 or 3 times and still nothing 

Correct - Ray and Sub are on S2 - but to reconfirm, Roam is not showing on S2 at all when searching, only when I bring up the network settings  

Do NOT factory reset everything. Leave the Ray alone!!

And  just so we are totally clear, you used the Roam on a different WiFI network but not as part of a different Sonos system, correct?

However, resetting the Roam should take care of either scenario.

What exactly happens when you try to add your reset Roam to your existing system I.e. the Ray?

I agree with @John B - do not factory reset the Ray and Sub. You could end up losing the entire original Sonos Household. I would focus on the Roam and reset that. Before setting it up next time first ensure the mobile Sonos App can see and play to your Ray and then go onto add the reset Roam to the setup using ‘Add Product’ in the Sonos App ‘Settings’.

I have just found out I have’t been Factory resetting it properly!! 

Everything is now working correctly 

Thank you everyone!