play 1 and era 300

Firstly, the “next” speaker has to be added to the same system. It’s a common mistake to create a new system. 
Secondly, as I recall, the Play:1 may only operate on 2.4ghz WiFi, and the era on 5ghz - I’ll check that in a moment. 
Also, Era is S2 only so if you’re running your Play:1 on the S1 app you need to move to S2.
what wifi router are you using?

It also may be your network/security version - see here:

https://support.sonos.com/en-gb/article/supported-wifi-modes-and-security-standards-for-sonos-products

Hello. It’s a Plusnet router.

With a play 5 ( gen 1) and the play 1 I had no issues. 

I’m a bit confused about you mentioning not getting the new speakers “on the same network”. Is the network the problem, or can you not get the new speaker added to the same system?

The Play 5 (Gen 1) is S1 only. The Era 300 is S2 only. You cannot make one system containing both speakers. See https://support.sonos.com/en-us/article/known-limitations-with-separate-s1-and-s2-sonos-systems

I love the way more info comes dribbling out… No mention of a Play:5 in your original post.  

You are on S1 if you have a Gen 1 play:5. The Era is not compatible with the S1 app. 

All sorted.

Thanks

How? Your answer may help others in a similar situation. 

The steps were :-

1. Did a factory reset on the Play1. Personally I think you may as well do it anyway rather than keep trying without doing it.
2. Started the addition of play 1 to the s2 system. I had to persevere as I had WiFi issues along the way, it could have been my WIFI playing up however.

thanks