diff --git a/new-lamassu-admin/src/pages/Customers/helper.js b/new-lamassu-admin/src/pages/Customers/helper.js
index 77c3732f..1842deef 100644
--- a/new-lamassu-admin/src/pages/Customers/helper.js
+++ b/new-lamassu-admin/src/pages/Customers/helper.js
@@ -434,7 +434,7 @@ const customerDataSchemas = {
   }),
   smsData: Yup.object()
     .shape({
-      phoneNumber: Yup.mixed().required()
+      phoneNumber: Yup.string().required()
     })
     .required()
 }