diff --git a/BTCPayServer/Controllers/UIStoresController.Settings.cs b/BTCPayServer/Controllers/UIStoresController.Settings.cs
index 23f72b8b1..f01ff9fe0 100644
--- a/BTCPayServer/Controllers/UIStoresController.Settings.cs
+++ b/BTCPayServer/Controllers/UIStoresController.Settings.cs
@@ -158,6 +158,8 @@ public partial class UIStoresController
             blob.CssUrl = null;
             needUpdate = true;
         }
+        if (!ModelState.IsValid)
+            return View(model);
 
         if (CurrentStore.SetStoreBlob(blob))
         {