I noticed this was asked back in 2018 but was never addressed. The refresh button has not been working in the app. The app is not frozen, just the refresh button. I have to completely exit the app and reopen before it refreshes. Why have the refresh button if it doesn’t work? This happens on both my iPhone XS Max and iPad.
iPhone XS
You could try restoring your phone to factory, Restore your iPhone, iPad, or iPod to factory settings - Apple Support and then set it up as a new device not from a backup. Make sure you make a backup of the device before restoring it. Test it after setting it up as new. If it does not work then I suggest you make a Genius Bar appointment to have the device checked by Apple.
did you try to force close the app?
My iPhone XS and my iPad, both on iOS 12.4 work just fine. I can tap on the refresh arrow in the upper right corner of the app and it refreshes. Swiping upwards only does not force closed the app. See this, How to force an app to close on your iPhone, iPad, or iPod touch - Apple Support
How do you force close? By swiping up to close? If so then yes. Nothings changed since at least a year ago. Does your refresh work?
Yes I’ve force closed many times and still the refresh button doesn’t work
Find my iPhone refresh button not refreshing
