Error saving user settings iOS

Hi,

I have written a widget which is available in the app store (apps.garmin.com/.../85c1e458-f8c0-4041-be71-f6694fa4cc39) where the user enters a number of configuration settings via the Connect IQ app. 

One user has just reported that they get an error ("There was a problem loading the settings for this device") whenever they try to save their settings :

I have never seen this error before and cannot recreate it.  It seems to be a problem in the Connect IQ app ability to save the settings rather than in my code (?) and would be grateful for any suggestions on what to do next.

The user has a Fenix 6 Pro running firmware 20.60 and are using an iPhone 13.