Null reference in TaskOrchestrationContext

We logged a null exception in class TaskOrchestrationContext in method ScheduleTaskInternal (line 118 not sure if reported correctly) using Microsoft.Azure.DurableTask.Core version 2.12.2

Could this be caused by a wrong usage of the framework? Checking the method I cannot see an obvious cause for it. Please advise.

Call stack is:
`{"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","level":0,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","level":1,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","level":2,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"DurableTask.Core.TaskOrchestrationContext+d__21.MoveNext","level":3,"line":118,"assembly":"DurableTask.Core, Version=2.12.0.0, Culture=neutral, PublicKeyToken=d53979610a6e89dd","fileName":"/_/src/DurableTask.Core/TaskOrchestrationContext.cs"},
{"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","level":4,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","level":5,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","level":6,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"DurableTask.Core.TaskOrchestrationContext+d__20`1.MoveNext","level":7,"line":94,"assembly":"DurableTask.Core, Version=2.12.0.0, Culture=neutral, PublicKeyToken=d53979610a6e89dd","fileName":"/_/src/DurableTask.Core/TaskOrchestrationContext.cs"},
{"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","level":8,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","level":9,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","level":10,"line":0,"assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e"},
{"method":"DurableTask.Core.TaskOrchestrationContext+d__19`1.MoveNext","level":11,"line":81,"assembly":"DurableTask.Core, Version=2.12.0.0, Culture=neutral, PublicKeyToken=d53979610a6e89dd","fileName":"/_/src/DurableTask.Core/TaskOrchestrationContext.cs"},
`