diff --git a/authentik/sources/oauth/api/source.py b/authentik/sources/oauth/api/source.py
index 805de67c65..f918d26967 100644
--- a/authentik/sources/oauth/api/source.py
+++ b/authentik/sources/oauth/api/source.py
@@ -59,7 +59,11 @@ class OAuthSourceSerializer(SourceSerializer):
 
     def validate(self, attrs: dict) -> dict:
         session = get_http_session()
-        source_type = registry.find_type(attrs["provider_type"])
+        provider_type_name = attrs.get(
+            "provider_type",
+            self.instance.provider_type if self.instance else None,
+        )
+        source_type = registry.find_type(provider_type_name)
 
         well_known = attrs.get("oidc_well_known_url") or source_type.oidc_well_known_url
         inferred_oidc_jwks_url = None
@@ -101,16 +105,15 @@ class OAuthSourceSerializer(SourceSerializer):
             config = jwks_config.json()
             attrs["oidc_jwks"] = config
 
-        provider_type = registry.find_type(attrs.get("provider_type", ""))
         for url in [
             "authorization_url",
             "access_token_url",
             "profile_url",
         ]:
-            if getattr(provider_type, url, None) is None:
+            if getattr(source_type, url, None) is None:
                 if url not in attrs:
                     raise ValidationError(
-                        f"{url} is required for provider {provider_type.verbose_name}"
+                        f"{url} is required for provider {source_type.verbose_name}"
                     )
         return attrs
 
diff --git a/authentik/sources/oauth/tests/test_api.py b/authentik/sources/oauth/tests/test_api.py
new file mode 100644
index 0000000000..0452bbe8bb
--- /dev/null
+++ b/authentik/sources/oauth/tests/test_api.py
@@ -0,0 +1,31 @@
+from django.urls import reverse
+from rest_framework.test import APITestCase
+
+from authentik.core.tests.utils import create_test_admin_user
+from authentik.lib.generators import generate_id
+from authentik.sources.oauth.models import OAuthSource
+
+
+class TestOAuthSourceAPI(APITestCase):
+    def setUp(self):
+        self.source = OAuthSource.objects.create(
+            name=generate_id(),
+            slug=generate_id(),
+            provider_type="openidconnect",
+            authorization_url="",
+            profile_url="",
+            consumer_key=generate_id(),
+        )
+        self.user = create_test_admin_user()
+
+    def test_patch_no_type(self):
+        self.client.force_login(self.user)
+        res = self.client.patch(
+            reverse("authentik_api:oauthsource-detail", kwargs={"slug": self.source.slug}),
+            {
+                "authorization_url": f"https://{generate_id()}",
+                "profile_url": f"https://{generate_id()}",
+                "access_token_url": f"https://{generate_id()}",
+            },
+        )
+        self.assertEqual(res.status_code, 200)