Live activity shows -- instead of seconds in SwiftUI

Question

Using Text (timerInterval: context.state.deliveryTimer, countsDown: true), it shows -- instead of seconds (1:30:--) when the iphone is locked, but its working just fine and countdown every second when the iphone is unlocked (1:30:50)(1:30:49)(1:30:48) and so on

how to solve this issue?

Here is the screenshot-