@Pattie-Liang Hello, please let me know if you can fix it with this process:
remove the widget from the screen
go to your app settings to the units
change the units to Celsius, close the settings
open the app settings, change the units to Fahrenheit, close the settings
add the widget to your screen
It's also good, to have Windy open only on your phone and not the desktop version in the web browser (sometimes hidden on your phone as well) at the same time.
I hope this will help to fix the issue, otherwise please send us the screenshot here or to support@windy.com by stating what version of Windy, device and OS are you using to further investigate the bug.
Have a nice day, Niki