Hey @RichieWild2810, welcome to the Sonos Community!
Apologies for the late response. Sorry to hear that you are unable to group the speakers as desired at the moment. There is no known issue regarding grouping, but you mentioning signing-in problems when trying to update might just be what we need to tackle first, as I suspect there is a missmatch between the speakers that prevents them to communicate properly with each other in order to join to a group. Here is what I would suggest to do:
1) Uninstall the Sonos App.
2) Visit sonos.com in the mobile device's primary browser and log out of any logged in Sonos accounts - if applicable.
3) Reboot the Mobile Device.
4) Reinstall the Sonos App and attempt the setup and update process again.
optional step 5 for iOS only) Clear the App Cache
* Navigate to Settings on the iOS Device, then visit General > iPhone/iPad Storage > Sonos > Delete App
* Reinstall the Sonos App from the App Store.
If an update is successfully, you should be able to group all speakers again. Should all fail, please reach out to our technical support who have tools at their disposal that will allow them to give you advice specific to your Sonos system and what it reports.
Hope that helps!