diff --git a/api/core/entities/provider_configuration.py b/api/core/entities/provider_configuration.py
index 9f8d06e322..0279725ff2 100644
--- a/api/core/entities/provider_configuration.py
+++ b/api/core/entities/provider_configuration.py
@@ -473,9 +473,21 @@ class ProviderConfiguration(BaseModel):
 
                     self.switch_preferred_provider_type(provider_type=ProviderType.CUSTOM, session=session)
                 else:
-                    # some historical data may have a provider record but not be set as valid
                     provider_record.is_valid = True
 
+                    if provider_record.credential_id is None:
+                        provider_record.credential_id = new_record.id
+                        provider_record.updated_at = naive_utc_now()
+
+                        provider_model_credentials_cache = ProviderCredentialsCache(
+                            tenant_id=self.tenant_id,
+                            identity_id=provider_record.id,
+                            cache_type=ProviderCredentialsCacheType.PROVIDER,
+                        )
+                        provider_model_credentials_cache.delete()
+
+                        self.switch_preferred_provider_type(provider_type=ProviderType.CUSTOM, session=session)
+
                 session.commit()
             except Exception:
                 session.rollback()
diff --git a/api/core/provider_manager.py b/api/core/provider_manager.py
index c538a557fb..ed34922346 100644
--- a/api/core/provider_manager.py
+++ b/api/core/provider_manager.py
@@ -196,6 +196,8 @@ class ProviderManager:
 
             if preferred_provider_type_record:
                 preferred_provider_type = ProviderType.value_of(preferred_provider_type_record.preferred_provider_type)
+            elif dify_config.EDITION == "CLOUD" and system_configuration.enabled:
+                preferred_provider_type = ProviderType.SYSTEM
             elif custom_configuration.provider or custom_configuration.models:
                 preferred_provider_type = ProviderType.CUSTOM
             elif system_configuration.enabled:
diff --git a/api/services/plugin/plugin_service.py b/api/services/plugin/plugin_service.py
index 55a3ffde78..ca83742d65 100644
--- a/api/services/plugin/plugin_service.py
+++ b/api/services/plugin/plugin_service.py
@@ -30,7 +30,7 @@ from core.plugin.impl.debugging import PluginDebuggingClient
 from core.plugin.impl.plugin import PluginInstaller
 from extensions.ext_database import db
 from extensions.ext_redis import redis_client
-from models.provider import Provider, ProviderCredential
+from models.provider import Provider, ProviderCredential, TenantPreferredModelProvider
 from models.provider_ids import GenericProviderID
 from services.enterprise.plugin_manager_service import (
     PluginManagerService,
@@ -534,6 +534,13 @@ class PluginService:
             plugin_id = plugin.plugin_id
             logger.info("Deleting credentials for plugin: %s", plugin_id)
 
+            session.execute(
+                delete(TenantPreferredModelProvider).where(
+                    TenantPreferredModelProvider.tenant_id == tenant_id,
+                    TenantPreferredModelProvider.provider_name.like(f"{plugin_id}/%"),
+                )
+            )
+
             # Delete provider credentials that match this plugin
             credential_ids = session.scalars(
                 select(ProviderCredential.id).where(
diff --git a/api/tests/unit_tests/core/entities/test_entities_provider_configuration.py b/api/tests/unit_tests/core/entities/test_entities_provider_configuration.py
index 82f98d07a3..5ebefcd8d2 100644
--- a/api/tests/unit_tests/core/entities/test_entities_provider_configuration.py
+++ b/api/tests/unit_tests/core/entities/test_entities_provider_configuration.py
@@ -734,7 +734,7 @@ def test_create_provider_credential_creates_provider_record_when_missing() -> No
 def test_create_provider_credential_marks_existing_provider_as_valid() -> None:
     configuration = _build_provider_configuration()
     session = Mock()
-    provider_record = SimpleNamespace(is_valid=False)
+    provider_record = SimpleNamespace(id="provider-1", is_valid=False, credential_id="existing-cred")
 
     with _patched_session(session):
         with patch.object(ProviderConfiguration, "_check_provider_credential_name_exists", return_value=False):
@@ -743,6 +743,25 @@ def test_create_provider_credential_marks_existing_provider_as_valid() -> None:
                     configuration.create_provider_credential({"api_key": "raw"}, "Main")
 
     assert provider_record.is_valid is True
+    assert provider_record.credential_id == "existing-cred"
+    session.commit.assert_called_once()
+
+
+def test_create_provider_credential_auto_activates_when_no_active_credential() -> None:
+    configuration = _build_provider_configuration()
+    session = Mock()
+    provider_record = SimpleNamespace(id="provider-1", is_valid=False, credential_id=None, updated_at=None)
+
+    with _patched_session(session):
+        with patch.object(ProviderConfiguration, "_check_provider_credential_name_exists", return_value=False):
+            with patch.object(ProviderConfiguration, "validate_provider_credentials", return_value={"api_key": "enc"}):
+                with patch.object(ProviderConfiguration, "_get_provider_record", return_value=provider_record):
+                    with patch("core.entities.provider_configuration.ProviderCredentialsCache"):
+                        with patch.object(ProviderConfiguration, "switch_preferred_provider_type"):
+                            configuration.create_provider_credential({"api_key": "raw"}, "Main")
+
+    assert provider_record.is_valid is True
+    assert provider_record.credential_id is not None
     session.commit.assert_called_once()