diff --git a/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceSignalForm.tsx b/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceSignalForm.tsx
index 1b7f74ada..7451e8e21 100644
--- a/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceSignalForm.tsx
+++ b/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceSignalForm.tsx
@@ -25,7 +25,10 @@ const UpdateWorkflowInstanceSignalForm = function (props: {
       signal: values.signal,
       reason: values.reason
     }).then((reason: any) => {
-      if (reason.error) {
+      if (!reason.ok) {
+        setErrorMsg(`HTTP error! status: ${reason.status}`);
+        setConfirmationMsg('');
+      } else if (reason.error) {
         setErrorMsg(reason.error);
         setConfirmationMsg('');
       } else {
diff --git a/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateForm.tsx b/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateForm.tsx
index 0f75ae313..2dce2f4cf 100644
--- a/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateForm.tsx
+++ b/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateForm.tsx
@@ -26,7 +26,10 @@ const UpdateWorkflowInstanceStateForm = function (props: {
       ),
       actionDescription: values.actionDescription
     }).then((reason: any) => {
-      if (reason.error) {
+      if (!reason.ok) {
+        setErrorMsg(`HTTP error! status: ${reason.status}`);
+        setConfirmationMsg('');
+      } else if (reason.error) {
         setErrorMsg(reason.error);
         setConfirmationMsg('');
       } else {
diff --git a/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateVariableForm.tsx b/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateVariableForm.tsx
index 3c06e4f8c..f3f546e39 100644
--- a/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateVariableForm.tsx
+++ b/nflow-explorer/src/workflow-instance/manage/UpdateWorkflowInstanceStateVariableForm.tsx
@@ -23,7 +23,10 @@ const UpdateWorkflowInstanceStateVariableForm = function (props: {
       },
       actionDescription: values.actionDescription
     }).then((reason: any) => {
-      if (reason.error) {
+      if (!reason.ok) {
+        setErrorMsg(`HTTP error! status: ${reason.status}`);
+        setConfirmationMsg('');
+      } else if (reason.error) {
         setErrorMsg(reason.error);
         setConfirmationMsg('');
       } else {