Hi @Bec 

Thanks for posting a question. 

Just to clarify, do you mean the time that is plotted on a horizontal line across the bottom of the graphs? If yes, then this scale changes according to the device settings. 

If you have your device time set to show on the 24-hour clock, then this will reflect in the App. 

Once you have applied this change, you may need to refresh the app for it to show. To refresh the App, just close it and re-open it again. 

Thanks, 

Stuart