diff --git a/KisaniCal/ISSUES.md b/KisaniCal/ISSUES.md
index 395e4fc..c7c2b3b 100644
--- a/KisaniCal/ISSUES.md
+++ b/KisaniCal/ISSUES.md
@@ -2229,3 +2229,24 @@ unwanted friction, not a fix — restored the KC-52 behavior where Finish
 skips the dialog only when `done == total` (nothing to override at that
 point). Partial-completion "Finish Anyway" still confirms. The
 always-visible progress dots from this issue's first change are untouched.
+
+## KC-64 — Xcode warning: deprecated `Activity.end(using:dismissalPolicy:)`
+
+Status: Implemented (not build-verified — no iOS runtime here)
+Reported by: User, Xcode warning screenshot ("'end(using:dismissalPolicy:)'
+was deprecated in iOS 16.2: Use end(content:dismissalPolicy:)")
+Area: Live Activities
+
+### Description
+Both Live Activity "stop" call sites called `activity.end(dismissalPolicy:
+.immediate)` with no content argument. ActivityKit has two overloads —
+`end(_:dismissalPolicy:)` (current) and the deprecated `end(using:
+dismissalPolicy:)` — and omitting the first argument entirely resolved to
+the deprecated one.
+
+### Change
+Pass `nil` explicitly as the unlabeled first argument so it binds to the
+non-deprecated overload: `activity.end(nil, dismissalPolicy: .immediate)`.
+
+Files: `KisaniCal/Managers/LiveActivityManager.swift`,
+`KisaniCalWidgets/StopCountdownIntent.swift`.
diff --git a/KisaniCal/Managers/LiveActivityManager.swift b/KisaniCal/Managers/LiveActivityManager.swift
index 0723c76..2756377 100644
--- a/KisaniCal/Managers/LiveActivityManager.swift
+++ b/KisaniCal/Managers/LiveActivityManager.swift
@@ -61,7 +61,7 @@ enum LiveActivityManager {
         Task {
             for activity in Activity<TaskActivityAttributes>.activities
             where activity.attributes.taskID == taskID {
-                await activity.end(dismissalPolicy: .immediate)
+                await activity.end(nil, dismissalPolicy: .immediate)
             }
         }
     }
diff --git a/KisaniCalWidgets/StopCountdownIntent.swift b/KisaniCalWidgets/StopCountdownIntent.swift
index fc2fcf8..8e10da6 100644
--- a/KisaniCalWidgets/StopCountdownIntent.swift
+++ b/KisaniCalWidgets/StopCountdownIntent.swift
@@ -19,7 +19,7 @@ struct StopCountdownIntent: LiveActivityIntent {
     func perform() async throws -> some IntentResult {
         for activity in Activity<TaskActivityAttributes>.activities
         where activity.attributes.taskID == taskID {
-            await activity.end(dismissalPolicy: .immediate)
+            await activity.end(nil, dismissalPolicy: .immediate)
         }
         return .result()
     }