Live Activity (Dynamic Island) suddenly stopped working without code changes

Hi everyone,

I am encountering an issue where my Live Activity (Dynamic Island) suddenly became invalid and failed to launch. It was working perfectly before, and I haven't modified any code since then.

My Environment:

• Xcode: 26.1.1
• Device iOS: 26.1
• Testing: I also tested on iOS 18, but the Live Activity fails to start there as well.

Here is my code:

1. Live Activity Manager (Start/Update/End):

func startLiveActivity() {
    // Initial static data
    let attributes = SimpleIslandAttributes(name: "Test Order")
    // Initial dynamic data
    let initialContentState = SimpleIslandState(message: "Preparing...")
    
    // Adapting for iOS 16.2+ new API (Content)
    let activityContent = ActivityContent(state: initialContentState, staleDate: nil)

    do {
        let activity = try Activity.request(
            attributes: attributes,
            content: activityContent,
            pushType: nil // Set to nil as remote push updates are not needed
        )
        print("Live Activity Started ID: \(activity.id)")
    } catch {
        print("Failed to start: \(error.localizedDescription)")
    }
}

// 2. Update Live Activity
func updateLiveActivity() {
    Task {
        let updatedState = SimpleIslandState(message: "Delivering 🚀")
        let updatedContent = ActivityContent(state: updatedState, staleDate: nil)
        
        // Iterate through all active Activities and update them
        for activity in Activity<SimpleIslandAttributes>.activities {
            await activity.update(updatedContent)
            print("Update")
        }
    }
}

// 3. End Live Activity
func endLiveActivity() {
    Task {
        let finalState = SimpleIslandState(message: "Delivered ✅")
        let finalContent = ActivityContent(state: finalState, staleDate: nil)
        
        for activity in Activity<SimpleIslandAttributes>.activities {
            // dismissalPolicy: .default (immediate), .after(...) (delayed), .immediate (no animation)
            await activity.end(finalContent, dismissalPolicy: .default)
            
            print("End")
        }
    }
}

The Models (Shared between App and Widget Extension):

 // 1. Define State (Dynamic data, changes over time, e.g., remaining delivery time)
public struct SimpleIslandState: Codable, Hashable {
    var message: String
}

// 2. Define Attributes (Static data, constant after start, e.g., Order ID)
public struct SimpleIslandAttributes: ActivityAttributes {
    public typealias ContentState = SimpleIslandState
    var name: String // e.g., "My Order"
}

The Widget Code:

//
//  SimpleIslandWidget.swift
//  ReadyGo
//
//  Created by Tang Yu on 2025/11/19.
//

import WidgetKit
import SwiftUI
import ActivityKit

struct SimpleIslandWidget: Widget {
    var body: some WidgetConfiguration {
        ActivityConfiguration(for: SimpleIslandAttributes.self) { context in
            // UI shown on the Lock Screen
            VStack {
                Text("Lock Screen Notification: \(context.state.message)")
            }
            .activityBackgroundTint(Color.cyan)
            .activitySystemActionForegroundColor(Color.black)

        } dynamicIsland: { context in
            // Inside Widget Extension
            DynamicIsland {
                // Expanded Region
                DynamicIslandExpandedRegion(.center) {
                    Text("Test") // Pure text only
                }
            } compactLeading: {
                Text("L") // Pure text only
            } compactTrailing: {
                Text("R") // Pure text only
            } minimal: {
                Text("M") // Pure text only
            }
        }
    }
}

Additional Info:

1. This is the minimal code setup I created for testing, but even this basic version is failing.
2. I have set NSSupportsLiveActivities (Supports Live Activities) to YES (true) in the Info.plist for both the Main App and the Widget Extension.

Has anyone experienced this? Any help would be appreciated.