diff --git a/flare_flutter/lib/flare_render_box.dart b/flare_flutter/lib/flare_render_box.dart
index 753fc9c..138ca72 100644
--- a/flare_flutter/lib/flare_render_box.dart
+++ b/flare_flutter/lib/flare_render_box.dart
@@ -164,10 +164,10 @@ abstract class FlareRenderBox extends RenderBox {
     if (isPlaying) {
       // Paint again
       if (_frameCallbackID != -1) {
-        SchedulerBinding.instance?.cancelFrameCallbackWithId(_frameCallbackID);
+        SchedulerBinding.instance.cancelFrameCallbackWithId(_frameCallbackID);
       }
       _frameCallbackID =
-          SchedulerBinding.instance?.scheduleFrameCallback(_beginFrame) ?? -1;
+          SchedulerBinding.instance.scheduleFrameCallback(_beginFrame);
     }
 
     final Canvas canvas = context.canvas;
@@ -269,7 +269,7 @@ abstract class FlareRenderBox extends RenderBox {
     } else {
       _lastFrameTime = _notPlayingFlag;
       if (_frameCallbackID != -1) {
-        SchedulerBinding.instance?.cancelFrameCallbackWithId(_frameCallbackID);
+        SchedulerBinding.instance.cancelFrameCallbackWithId(_frameCallbackID);
       }
     }
   }