Garmin VivoSmart 5 recent firmware?

Hi All  I'm a new Garmin user  and new to the forum.  I've bought a VivoSmart 5 and had quite some fun connecting ot to Bluetooth initially, but mostly works ok now apart from......  The main reason I bought it was for sleep tracking.  Often in the mornings, the connect app says "No sleep data" when I've worn the watch all night and it's been fully charged.

Today it also said no data, so I synced manually (Home/top right icon), but still no data, so synced again.  Still no data.  About an hour later, I checked again and the score was there.

First thought was the connect app/watch firmware.  The connect app is up to date and the latest firmware on the Garmin site is 3.23 and 1-year old beta version.  My watch says the version is 3.29, so I'm a little confused as to what the latest version is!

The connect app has no battery restrictions.

Connect is running on a Xiaomi Mi 14 Ultra phone with Android 15

Does anyone where I can get the latest version of the watch firmware?

Thanks for reading....

Steve