how do i resolve this error?

[Dilshan97]

This error comes when we use the animations we created. but these animations work fine in the timeline. how to fix this issue?

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E/flutter (18251): [ERROR:flutter/shell/common/shell.cc(199)] Dart Error: Unhandled exception:
E/flutter (18251): Looking up a deactivated widget's ancestor is unsafe.
E/flutter (18251): At this point the state of the widget's element tree is no longer stable.
E/flutter (18251): To safely refer to a widget's ancestor in its dispose() method, save a reference to the ancestor by calling dependOnInheritedWidgetOfExactType() in the widget's didChangeDependencies() method.
E/flutter (18251): #0 Element._debugCheckStateIsActiveForAncestorLookup. (package:flutter/src/widgets/framework.dart:3508:9)
E/flutter (18251): #1 Element._debugCheckStateIsActiveForAncestorLookup (package:flutter/src/widgets/framework.dart:3522:6)
E/flutter (18251): #2 Element.findAncestorStateOfType (package:flutter/src/widgets/framework.dart:3641:12)
E/flutter (18251): #3 Navigator.of (package:flutter/src/widgets/navigator.dart:1492:19)
E/flutter (18251): #4 _CustomSplashState.build. (package:custom_splash/custom_splash.dart:122:23)
E/flutter (18251): #5 _RootZone.runUnary (dart:async/zone.dart:1381:54)
E/flutter (18251): #6 _FutureListener.handleValue (dart:async/future_impl.dart:139:18)
E/flutter (18251): #7 Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:680:45)
E/flutter (18251): #8 Future._propagateToListeners (dart:async/future_impl.dart:709:32)
E/flutter (18251): #9 Future._complete (dart:async/future_impl.dart:514:7)
E/flutter (18251): #10 new Future.delayed. (dart:async/future.dart:313:16)
E/flutter (18251): #11 Timer._createTimer. (dart:async-patch/timer_patch.dart:23:15)
E/flutter (18251): #12 _Timer._runTimers (dart:isolate-patch/timer_impl.dart:384:19)
E/flutter (18251): #13 _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:418:5)
E/flutter (18251): #14 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:174:12)