diff --git a/api/controllers/console/auth/activate.py b/api/controllers/console/auth/activate.py
index eedb2854345..65e278edb54 100644
--- a/api/controllers/console/auth/activate.py
+++ b/api/controllers/console/auth/activate.py
@@ -2,15 +2,17 @@ from flask import request
 from flask_restx import Resource
 from pydantic import BaseModel, Field, field_validator
 
+from configs import dify_config
 from constants.languages import supported_language
 from controllers.common.schema import register_schema_models
 from controllers.console import console_ns
-from controllers.console.error import AlreadyActivateError
+from controllers.console.error import AccountInFreezeError, AlreadyActivateError
 from extensions.ext_database import db
 from libs.datetime_utils import naive_utc_now
 from libs.helper import EmailStr, timezone
 from models import AccountStatus
 from services.account_service import RegisterService
+from services.billing_service import BillingService
 
 
 class ActivateCheckQuery(BaseModel):
@@ -120,9 +122,12 @@ class ActivateApi(Resource):
         if invitation is None:
             raise AlreadyActivateError()
 
+        account = invitation["account"]
+        if dify_config.BILLING_ENABLED and BillingService.is_email_in_freeze(account.email):
+            raise AccountInFreezeError()
+
         RegisterService.revoke_token(args.workspace_id, normalized_request_email, args.token)
 
-        account = invitation["account"]
         account.name = args.name
 
         account.interface_language = args.interface_language
diff --git a/api/tests/unit_tests/controllers/console/auth/test_account_activation.py b/api/tests/unit_tests/controllers/console/auth/test_account_activation.py
index 0fb0ebc330a..79169cfce7e 100644
--- a/api/tests/unit_tests/controllers/console/auth/test_account_activation.py
+++ b/api/tests/unit_tests/controllers/console/auth/test_account_activation.py
@@ -14,7 +14,7 @@ import pytest
 from flask import Flask
 
 from controllers.console.auth.activate import ActivateApi, ActivateCheckApi
-from controllers.console.error import AlreadyActivateError
+from controllers.console.error import AccountInFreezeError, AlreadyActivateError
 from models.account import AccountStatus
 
 
@@ -255,6 +255,47 @@ class TestActivateApi:
             with pytest.raises(AlreadyActivateError):
                 api.post()
 
+    @patch("controllers.console.auth.activate.dify_config.BILLING_ENABLED", True)
+    @patch("controllers.console.auth.activate.BillingService.is_email_in_freeze")
+    @patch("controllers.console.auth.activate.RegisterService.get_invitation_if_token_valid")
+    @patch("controllers.console.auth.activate.RegisterService.revoke_token")
+    @patch("controllers.console.auth.activate.db")
+    def test_activation_rejects_account_in_billing_freeze(
+        self,
+        mock_db,
+        mock_revoke_token,
+        mock_get_invitation,
+        mock_is_email_in_freeze,
+        app: Flask,
+        mock_invitation,
+        mock_account,
+    ):
+        """Frozen deleted-account emails cannot be reactivated through invitation links."""
+        mock_account.email = "Invitee@Example.com"
+        mock_get_invitation.return_value = mock_invitation
+        mock_is_email_in_freeze.return_value = True
+
+        with app.test_request_context(
+            "/activate",
+            method="POST",
+            json={
+                "workspace_id": "workspace-123",
+                "email": "invitee@example.com",
+                "token": "valid_token",
+                "name": "John Doe",
+                "interface_language": "en-US",
+                "timezone": "UTC",
+            },
+        ):
+            api = ActivateApi()
+            with pytest.raises(AccountInFreezeError):
+                api.post()
+
+        mock_is_email_in_freeze.assert_called_once_with("Invitee@Example.com")
+        mock_revoke_token.assert_not_called()
+        mock_db.session.commit.assert_not_called()
+        assert mock_account.status == AccountStatus.PENDING
+
     @patch("controllers.console.auth.activate.RegisterService.get_invitation_with_case_fallback")
     @patch("controllers.console.auth.activate.RegisterService.revoke_token")
     @patch("controllers.console.auth.activate.db")