diff --git a/package.json b/package.json
index c3e45703..669b9c96 100644
--- a/package.json
+++ b/package.json
@@ -10,7 +10,7 @@
     "@fastify/cors": "^8.2.0",
     "@fastify/formbody": "^7.3.0",
     "@fastify/swagger": "^8.1.0",
-    "@prisma/client": "4",
+    "@prisma/client": "4.16.2",
     "@sentry/node": "^7.9.0",
     "@sentry/tracing": "^7.9.0",
     "@simplewebauthn/server": "^5.4.0",
@@ -54,7 +54,7 @@
     "husky": "^4.3.0",
     "lint-staged": "^10.5.1",
     "prettier": "^2.1.2",
-    "prisma": "4",
+    "prisma": "4.16.2",
     "ts-node": "^9.0.0"
   },
   "scripts": {
diff --git a/src/common/meiling/identity/user.ts b/src/common/meiling/identity/user.ts
index 32f382a4..e7314e3f 100644
--- a/src/common/meiling/identity/user.ts
+++ b/src/common/meiling/identity/user.ts
@@ -1,4 +1,4 @@
-import { Email, Group, OAuthTokenType, Phone, prisma, User as UserModel, OAuthClient } from '@prisma/client';
+import { Email, Group, OAuthTokenType, Phone, User as UserModel, OAuthClient } from '@prisma/client';
 import { VerifiedAuthenticationResponse, VerifiedRegistrationResponse } from '@simplewebauthn/server/./dist';
 import { AttestationFormat } from '@simplewebauthn/server/dist/helpers/decodeAttestationObject';
 import { CredentialDeviceType } from '@simplewebauthn/typescript-types';
diff --git a/src/routes/v1/admin/users/index.ts b/src/routes/v1/admin/users/index.ts
index c7ca9617..e6ee72c4 100644
--- a/src/routes/v1/admin/users/index.ts
+++ b/src/routes/v1/admin/users/index.ts
@@ -264,10 +264,38 @@ const userAdminHandler = (app: FastifyInstance, opts: FastifyPluginOptions, done
       // actually delete if admin requested permanent deletion
       // note: this could lead possible uuid collision for other apps.
       if (permanent) {
-        await getPrismaClient().user.delete({
-          where: {
-            id: uuid,
-          },
+        const userId = uuid;
+        await getPrismaClient().$transaction(async (tx) => {
+          await tx.email.deleteMany({ where: { userId } });
+          await tx.phone.deleteMany({ where: { userId } });
+          await tx.authentication.deleteMany({ where: { userId } });
+          await tx.oAuthClientSecrets.deleteMany({ where: { userId } });
+          await tx.policyConsent.deleteMany({ where: { userId } });
+
+          const authorizations = await tx.oAuthClientAuthorization.findMany({ where: { userId } });
+          for (const auth of authorizations) {
+            await tx.oAuthToken.deleteMany({ where: { authorizationId: auth.id } });
+          }
+          await tx.oAuthClientAuthorization.deleteMany({ where: { userId } });
+
+          await tx.user.update({
+            where: { id: userId },
+            data: { groups: { set: [] } },
+          });
+
+          const ownedClients = await tx.oAuthClient.findMany({ where: { owners: { some: { id: userId } } } });
+          for (const client of ownedClients) {
+            await tx.oAuthClient.update({
+              where: { id: client.id },
+              data: {
+                owners: {
+                  disconnect: { id: userId },
+                },
+              },
+            });
+          }
+
+          await tx.user.delete({ where: { id: userId } });
         });
       }
 
diff --git a/yarn.lock b/yarn.lock
index c4f76b4e..be7e202f 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -160,22 +160,22 @@
     pvtsutils "^1.3.2"
     tslib "^2.4.0"
 
-"@prisma/client@4":
-  version "4.6.1"
-  resolved "https://registry.yarnpkg.com/@prisma/client/-/client-4.6.1.tgz#e8e1d347ecbff44158d21b6591bb99650c8503a8"
-  integrity sha512-M1+NNrMzqaOIxT7PBGcTs3IZo7d1EW/+gVQd4C4gUgWBDGgD9AcIeZnUSidgWClmpMSgVUdnVORjsWWGUameYA==
+"@prisma/client@4.16.2":
+  version "4.16.2"
+  resolved "https://registry.yarnpkg.com/@prisma/client/-/client-4.16.2.tgz#3bb9ebd49b35c8236b3d468d0215192267016e2b"
+  integrity sha512-qCoEyxv1ZrQ4bKy39GnylE8Zq31IRmm8bNhNbZx7bF2cU5aiCCnSa93J2imF88MBjn7J9eUQneNxUQVJdl/rPQ==
   dependencies:
-    "@prisma/engines-version" "4.6.1-3.694eea289a8462c80264df36757e4fdc129b1b32"
+    "@prisma/engines-version" "4.16.1-1.4bc8b6e1b66cb932731fb1bdbbc550d1e010de81"
 
-"@prisma/engines-version@4.6.1-3.694eea289a8462c80264df36757e4fdc129b1b32":
-  version "4.6.1-3.694eea289a8462c80264df36757e4fdc129b1b32"
-  resolved "https://registry.yarnpkg.com/@prisma/engines-version/-/engines-version-4.6.1-3.694eea289a8462c80264df36757e4fdc129b1b32.tgz#90a71bbdfd5172fc674009346a6ad6b84410cc0a"
-  integrity sha512-HUCmkXAU2jqp2O1RvNtbE+seLGLyJGEABZS/R38rZjSAafAy0WzBuHq+tbZMnD+b5OSCsTVtIPVcuvx1ySxcWQ==
+"@prisma/engines-version@4.16.1-1.4bc8b6e1b66cb932731fb1bdbbc550d1e010de81":
+  version "4.16.1-1.4bc8b6e1b66cb932731fb1bdbbc550d1e010de81"
+  resolved "https://registry.yarnpkg.com/@prisma/engines-version/-/engines-version-4.16.1-1.4bc8b6e1b66cb932731fb1bdbbc550d1e010de81.tgz#d3b5dcf95b6d220e258cbf6ae19b06d30a7e9f14"
+  integrity sha512-q617EUWfRIDTriWADZ4YiWRZXCa/WuhNgLTVd+HqWLffjMSPzyM5uOWoauX91wvQClSKZU4pzI4JJLQ9Kl62Qg==
 
-"@prisma/engines@4.6.1":
-  version "4.6.1"
-  resolved "https://registry.yarnpkg.com/@prisma/engines/-/engines-4.6.1.tgz#ae31309cc0f600f2da22708697b3be4eb1e46f9e"
-  integrity sha512-3u2/XxvxB+Q7cMXHnKU0CpBiUK1QWqpgiBv28YDo1zOIJE3FCF8DI2vrp6vuwjGt5h0JGXDSvmSf4D4maVjJdw==
+"@prisma/engines@4.16.2":
+  version "4.16.2"
+  resolved "https://registry.yarnpkg.com/@prisma/engines/-/engines-4.16.2.tgz#5ec8dd672c2173d597e469194916ad4826ce2e5f"
+  integrity sha512-vx1nxVvN4QeT/cepQce68deh/Turxy5Mr+4L4zClFuK1GlxN3+ivxfuv+ej/gvidWn1cE1uAhW7ALLNlYbRUAw==
 
 "@sentry/core@7.20.1":
   version "7.20.1"
@@ -2449,12 +2449,12 @@ prettier@^2.1.2:
   resolved "https://registry.yarnpkg.com/prettier/-/prettier-2.7.1.tgz#e235806850d057f97bb08368a4f7d899f7760c64"
   integrity sha512-ujppO+MkdPqoVINuDFDRLClm7D78qbDt0/NR+wp5FqEZOoTNAjPHWj17QRhu7geIHJfcNhRk1XVQmF8Bp3ye+g==
 
-prisma@4:
-  version "4.6.1"
-  resolved "https://registry.yarnpkg.com/prisma/-/prisma-4.6.1.tgz#6c85fb667abed006a6b849c9c1ddd81d3f071b87"
-  integrity sha512-BR4itMCuzrDV4tn3e2TF+nh1zIX/RVU0isKtKoN28ADeoJ9nYaMhiuRRkFd2TZN8+l/XfYzoRKyHzUFXLQhmBQ==
+prisma@4.16.2:
+  version "4.16.2"
+  resolved "https://registry.yarnpkg.com/prisma/-/prisma-4.16.2.tgz#469e0a0991c6ae5bcde289401726bb012253339e"
+  integrity sha512-SYCsBvDf0/7XSJyf2cHTLjLeTLVXYfqp7pG5eEVafFLeT0u/hLFz/9W196nDRGUOo1JfPatAEb+uEnTQImQC1g==
   dependencies:
-    "@prisma/engines" "4.6.1"
+    "@prisma/engines" "4.16.2"
 
 process-warning@^1.0.0:
   version "1.0.0"