diff --git a/src/components/portal/login-flow.tsx b/src/components/portal/login-flow.tsx
index 16094f0..775b36a 100644
--- a/src/components/portal/login-flow.tsx
+++ b/src/components/portal/login-flow.tsx
@@ -85,7 +85,11 @@ export function LoginFlow() {
           replace("identify");
         }
       })
-      .catch(() => { setFlash("Sign-in with that provider didn't complete. Try again."); replace("identify"); });
+      .catch((e) => {
+        console.error("[oauth] completeOAuthLogin failed:", e);
+        setFlash(`Google sign-in didn't complete: ${(e as Error)?.message ?? "unknown error"}`);
+        replace("identify");
+      });
   }, [ready, completeOAuthLogin, router]);
 
   /* ---- auth resolution ---- */