TfsTestPlansAndSuitesMigrationProcessor fails with Sequence contains more than one element

[fseerup]

When using this :

      {
        "ProcessorType": "TfsTestPlansAndSuitesMigrationProcessor",
        "Enabled": true,
        "OnlyElementsWithTag": "",
        "TestPlanQuery": null,
        "RemoveAllLinks": false,
        "MigrationDelay": 0,
        "RemoveInvalidTestSuiteLinks": false,
        "FilterCompleted": false,
        "SourceName": "Source",
        "TargetName": "Target"
      }

I get this error, which I am not sure is a Bug, or a problem in my Test Plans (and if so, how to fix):

       Error while running TfsTestPlansAndSuitesMigrationProcessor
System.InvalidOperationException: Sequence contains more than one element
   at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source)
   at MigrationTools.Processors.TfsTestPlansAndSuitesMigrationProcessor.FindTestPlan(String planName, Int32 sourcePlanId) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsTestPlansAndSuitesMigrationProcessor.cs:line 610
   at MigrationTools.Processors.TfsTestPlansAndSuitesMigrationProcessor.ProcessTestPlan(ITestPlan sourcePlan) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsTestPlansAndSuitesMigrationProcessor.cs:line 844
   at MigrationTools.Processors.TfsTestPlansAndSuitesMigrationProcessor.InternalExecute() in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsTestPlansAndSuitesMigrationProcessor.cs:line 113
   at MigrationTools.Processors.Infrastructure.Processor.Execute() in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools\Processors\Infrastructure\Processor.cs:line 99

[MrHinsh]

You have two test plans with the same name in the Source. Update them to be different and you will pass this.

[fseerup]

When querying using Work Item Type = Test Plan, I only get 2 items , and with different names. Strange

[fseerup]

Also fails when just selecting one plan using:
"TestPlanQuery": "PlanID IN ('3')",