diff --git a/app/src/main/java/com/example/updateapp/views/activites/LoginActivity.java b/app/src/main/java/com/example/updateapp/views/activites/LoginActivity.java
index 8700ad9..f872e4a 100644
--- a/app/src/main/java/com/example/updateapp/views/activites/LoginActivity.java
+++ b/app/src/main/java/com/example/updateapp/views/activites/LoginActivity.java
@@ -55,6 +55,13 @@ protected void onCreate(Bundle savedInstanceState) {
         setContentView(binding.getRoot());
 
         auth = FirebaseAuth.getInstance();
+
+        // Handle prefilled email from OTPActivity redirect
+        String prefilledEmail = getIntent().getStringExtra("prefilled_email");
+        if (prefilledEmail != null && !prefilledEmail.isEmpty()) {
+            binding.edtEmail.setText(prefilledEmail);
+        }
+
         googleBtn = findViewById(R.id.google_btn);
         emailBtn = findViewById(R.id.email_btn);
 
diff --git a/app/src/main/java/com/example/updateapp/views/activites/OTPActivity.java b/app/src/main/java/com/example/updateapp/views/activites/OTPActivity.java
index 918ed05..7cf80d6 100644
--- a/app/src/main/java/com/example/updateapp/views/activites/OTPActivity.java
+++ b/app/src/main/java/com/example/updateapp/views/activites/OTPActivity.java
@@ -186,9 +186,9 @@ private void verifyCredential(PhoneAuthCredential credential) {
                                     String msg = e != null ? e.getMessage() : "Unknown linking error";
 
                                     if (e instanceof FirebaseAuthUserCollisionException) {
-                                        Toast.makeText(OTPActivity.this,
-                                                "This email is already registered with a different account. Please login with that email or use another email.",
-                                                Toast.LENGTH_LONG).show();
+                                        // Email already exists with different account.
+                                        // Save phone-based user data to Firestore first, then redirect to login.
+                                        saveUserToFirestoreOnCollision(uid, name, email, number, password);
                                     } else {
                                         Toast.makeText(OTPActivity.this,
                                                 "Failed to link email: " + msg,
@@ -199,6 +199,49 @@ private void verifyCredential(PhoneAuthCredential credential) {
                 });
     }
 
+    private void saveUserToFirestoreOnCollision(String uid, String name, String email, String number, String password) {
+        if (name == null) name = "";
+        if (email == null) email = "";
+        if (number == null) number = "";
+        if (password == null) password = "";
+
+        UserModel user = new UserModel(
+                name,
+                email,
+                number,
+                password,
+                "https://firebasestorage.googleapis.com/v0/b/earning-b8942.firebasestorage.app/o/account.png?alt=media&token=***"
+        );
+
+        if (dialog.isShowing()) dialog.dismiss();
+
+        firestore.collection("users")
+                .document(uid)
+                .set(user)
+                .addOnSuccessListener(unused -> {
+                    // User data saved successfully. Now sign out and redirect to login.
+                    auth.signOut();
+                    Toast.makeText(OTPActivity.this,
+                            "An account with this email already exists. Please login with your email and password.",
+                            Toast.LENGTH_LONG).show();
+                    Intent intent = new Intent(OTPActivity.this, LoginActivity.class);
+                    intent.putExtra("prefilled_email", email);
+                    startActivity(intent);
+                    finish();
+                })
+                .addOnFailureListener(e -> {
+                    // Failed to save - still redirect to login with email prefilled.
+                    auth.signOut();
+                    Toast.makeText(OTPActivity.this,
+                            "Failed to link email: " + e.getMessage() + ". Please login with your existing account.",
+                            Toast.LENGTH_LONG).show();
+                    Intent intent = new Intent(OTPActivity.this, LoginActivity.class);
+                    intent.putExtra("prefilled_email", email);
+                    startActivity(intent);
+                    finish();
+                });
+    }
+
     private void saveUserToFirestoreAndContinue(String uid, String name, String email, String number, String password) {
 
         if (name == null) name = "";