A. 1. Ensure that you are connected to the internet when entering weigh-in data, as the app may require a connection to save changes. 2. After entering your weight, wait for a confirmation message that indicates the data has been saved. 3. Check the app's settings to see if there are any options related to data saving or syncing that need to be enabled.

B. 1. If the app continues to fail to save data, try uninstalling and reinstalling it to reset any potential bugs.