diff --git a/app/javascript/submission_form/kba_step.vue b/app/javascript/submission_form/kba_step.vue
index 253b9636..03c7431a 100644
--- a/app/javascript/submission_form/kba_step.vue
+++ b/app/javascript/submission_form/kba_step.vue
@@ -497,10 +497,10 @@ export default {
           body: JSON.stringify(payload)
         })
 
-        if (!resp.ok) throw new Error('Failed to start KBA')
-
         const data = await resp.json()
 
+        if (!resp.ok) throw new Error(data.error || 'Failed to start KBA')
+
         if (data.result && data.result.action === 'FAIL') {
           if (data.result.detail === 'NO MATCH') {
             throw new Error('Unfortunately, we were unable to start Knowledge Based Authentication with the details provided. Please review and confirm that all your personal details are correct.')