New marker information retaining information from the previous marker.

Vuforia SDK Version: 8.3.8 - Description with steps to reproduce: On my cloud recognition project, I have a marker with the word Flower and the image Flower. Then I go to another marker that should have the word Dog and the dog image, but he keeps bringing a flower. Only after 4 or 5 attempts they bring the dog. What I'm missing? I tried to fix it and I fixed it in parts. I put this line of code OnTrackingLost: TrackerManager.Instance.GetTracker().GetTargetFinder().ClearTrackables(false); It works but I'm getting these errors: Exception in callback: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.InvalidOperationException: Collection was modified; enumeration operation may not execute. at System.Collections.Generic.Dictionary`2+ValueCollection+Enumerator[TKey,TValue].MoveNext () [0x00013] in :0 at System.Linq.Enumerable+WhereEnumerableIterator`1[TSource].MoveNext () [0x0004e] in :0 at Vuforia.StateManager.UpdateTrackableStates (Vuforia.TrackerData+TrackableResultData[] trackableResults) [0x0010c] in <21bfe61d2ac241f6a9131b858645aad9>:0 at ... - Development OS (Mac OS X, Windows, Linux): Mac OS X - Mobile OS and Version: Android 8 - Mobile Device Manufacturer and Model name: Sansumg S7 - Do the Vuforia Sample Applications show the same behavior?: The Sample Applications probably is in a newest version then my.