Group texting - Windows 10 (Redstone, latest ver) how do I get it to send to a message to all of the groups I have created?

[Smiggyy]

Group texting - Windows 10 (Redstone, latest ver)

I have created 3 x groups containing 10 people x 2, 3rd has 9.
When I 'message all' via the bottom option of the group in 'people' it only sends to the first listed member of the group, nobody else?

This is the same whether I'm on Data or WiFi.
Anyone else experiencing the same or have a solution/workaround by any chance?

I run a footy team so ability to text all parents regularly is a must!
Lumia 640 LTE

 

[Smiggyy]

Resolved in latest update, thanks!