diff --git a/src/frontend/src/components/forms/fields/RelatedModelField.tsx b/src/frontend/src/components/forms/fields/RelatedModelField.tsx
index 22eadbc988..18816190dd 100644
--- a/src/frontend/src/components/forms/fields/RelatedModelField.tsx
+++ b/src/frontend/src/components/forms/fields/RelatedModelField.tsx
@@ -59,12 +59,17 @@ export function RelatedModelField({
     if (field.value === pk) return;
 
     if (
-      field.value !== null &&
-      field.value !== undefined &&
-      field.value !== ''
+      field?.value !== null &&
+      field?.value !== undefined &&
+      field?.value !== ''
     ) {
       const url = `${definition.api_url}${field.value}/`;
 
+      if (!url) {
+        setPk(null);
+        return;
+      }
+
       api.get(url).then((response) => {
         let pk_field = definition.pk_field ?? 'pk';
         if (response.data && response.data[pk_field]) {