diff --git a/durablefunctionsmonitor.dotnetbackend/Common/DetailedOrchestrationStatus.cs b/durablefunctionsmonitor.dotnetbackend/Common/DetailedOrchestrationStatus.cs
index e71f753..9c2b7eb 100644
--- a/durablefunctionsmonitor.dotnetbackend/Common/DetailedOrchestrationStatus.cs
+++ b/durablefunctionsmonitor.dotnetbackend/Common/DetailedOrchestrationStatus.cs
@@ -109,7 +109,7 @@ internal static async Task<string> GetParentInstanceIdDirectlyFromTable(IDurable
                 // Also need to put it under a feature switch, as it still might be a performance issue
 
                 string featureFlags = Environment.GetEnvironmentVariable(EnvVariableNames.AzureWebJobsFeatureFlags);
-                bool isDisabled = featureFlags.Contains(Globals.DfMonDisableNewParentIdResolutionAlgorithm);
+                bool isDisabled = featureFlags == null ? false : featureFlags.Contains(Globals.DfMonDisableNewParentIdResolutionAlgorithm);
                 if (isDisabled)
                 {
                     return null;
diff --git a/durablefunctionsmonitor.dotnetisolated.core/Common/DetailedOrchestrationStatus.cs b/durablefunctionsmonitor.dotnetisolated.core/Common/DetailedOrchestrationStatus.cs
index 28d54fe..bed3ce4 100644
--- a/durablefunctionsmonitor.dotnetisolated.core/Common/DetailedOrchestrationStatus.cs
+++ b/durablefunctionsmonitor.dotnetisolated.core/Common/DetailedOrchestrationStatus.cs
@@ -108,7 +108,7 @@ internal static async Task<string> GetParentInstanceIdDirectlyFromTable(DurableT
                 // Also need to put it under a feature switch, as it still might be a performance issue
 
                 string featureFlags = Environment.GetEnvironmentVariable(EnvVariableNames.AzureWebJobsFeatureFlags);
-                bool isDisabled = featureFlags.Contains(Globals.DfMonDisableNewParentIdResolutionAlgorithm);
+                bool isDisabled = featureFlags == null ? false : featureFlags.Contains(Globals.DfMonDisableNewParentIdResolutionAlgorithm);
                 if (isDisabled)
                 {
                     return null;