getExpoPushTokenAsync can't work on first time iOS . need restart ?

I have install expo-notification to use on my Bare workflow app .
On android it work as expected .
How ever , on iOS (xcode 11) . the getExpoPushTokenAsync just hang on the first time opening app ( notification is allowed ) .
The only way to get it work is restart the app ( kill app then re open ) .
Any one know the root cause . Please share