diff --git a/quickstep/src/com/android/quickstep/views/DigitalWellBeingToast.kt b/quickstep/src/com/android/quickstep/views/DigitalWellBeingToast.kt
index 731b008..0ab36c9 100644
--- a/quickstep/src/com/android/quickstep/views/DigitalWellBeingToast.kt
+++ b/quickstep/src/com/android/quickstep/views/DigitalWellBeingToast.kt
@@ -257,7 +257,7 @@
         task: Task,
         appUsageLimitTimeMs: Long,
         appRemainingTimeMs: Long
-    ): String =
+    ): String? =
         if (appUsageLimitTimeMs >= 0 && appRemainingTimeMs >= 0)
             container
                 .asContext()