diff --git a/ui/src/app/archived-workflows/components/archived-workflow-filters/archived-workflow-filters.tsx b/ui/src/app/archived-workflows/components/archived-workflow-filters/archived-workflow-filters.tsx
index 33a6a7ada6b4..111c2a52d404 100644
--- a/ui/src/app/archived-workflows/components/archived-workflow-filters/archived-workflow-filters.tsx
+++ b/ui/src/app/archived-workflows/components/archived-workflow-filters/archived-workflow-filters.tsx
@@ -199,9 +199,8 @@ export class ArchivedWorkflowFilters extends React.Component<ArchivedWorkflowFil
         });
     }
 
-    private fetchArchivedWorkflowsLabels(key: string): Promise<any> {
-        return services.archivedWorkflows.listLabelValues(key, this.props.namespace).then(list => {
-            return list.items.map(i => key + '=' + i).sort((a, b) => a.localeCompare(b));
-        });
+    private async fetchArchivedWorkflowsLabels(key: string): Promise<string[]> {
+        const labels = await services.archivedWorkflows.listLabelValues(key, this.props?.namespace);
+        return labels.items.map(i => key + '=' + i).sort((a, b) => a.localeCompare(b));
     }
 }
diff --git a/ui/src/app/shared/services/archived-workflows-service.ts b/ui/src/app/shared/services/archived-workflows-service.ts
index 1159fcd22ae0..c6697f1b9611 100644
--- a/ui/src/app/shared/services/archived-workflows-service.ts
+++ b/ui/src/app/shared/services/archived-workflows-service.ts
@@ -39,12 +39,12 @@ export class ArchivedWorkflowsService {
         }
     }
 
-    public listLabelValues(key: string, namespace: string) {
-        if (namespace === '') {
-            return requests.get(`api/v1/archived-workflows-label-values?listOptions.labelSelector=${key}`).then(res => res.body as models.Labels);
-        } else {
-            return requests.get(`api/v1/archived-workflows-label-values?namespace=${namespace}&listOptions.labelSelector=${key}`).then(res => res.body as models.Labels);
+    public async listLabelValues(key: string, namespace: string): Promise<models.Labels> {
+        let url = `api/v1/archived-workflows-label-values?listOptions.labelSelector=${key}`;
+        if (namespace !== '') {
+            url += `&namespace=${namespace}`;
         }
+        return (await requests.get(url)).body as models.Labels;
     }
 
     public resubmit(uid: string, namespace: string) {