diff --git a/src/server.js b/src/server.js
index 27d5514..a91f94f 100644
--- a/src/server.js
+++ b/src/server.js
@@ -31,6 +31,48 @@ app.get('/healthz', (_, res) => {
   res.json({ status: 'ok' });
 });
 
+function buildDefaultFullName(email) {
+  const localPart = email.split('@')[0]?.trim();
+  if (!localPart) {
+    return 'Новый пользователь';
+  }
+
+  return localPart
+    .replace(/[._-]+/g, ' ')
+    .split(' ')
+    .filter(Boolean)
+    .map((part) => part.charAt(0).toUpperCase() + part.slice(1))
+    .join(' ');
+}
+
+async function resolveUserForMessenger({ userId, email }) {
+  if (userId) {
+    const byId = await prisma.user.findUnique({ where: { id: userId } });
+    if (byId) {
+      return byId;
+    }
+  }
+
+  if (!email) {
+    return null;
+  }
+
+  const normalizedEmail = email.trim().toLowerCase();
+  if (!normalizedEmail) {
+    return null;
+  }
+
+  return prisma.user.upsert({
+    where: { email: normalizedEmail },
+    update: {},
+    create: {
+      email: normalizedEmail,
+      fullName: buildDefaultFullName(normalizedEmail),
+      role: 'CLIENT',
+    },
+  });
+}
+
 app.post('/bot/messenger-login', async (req, res) => {
   const webhookToken = process.env.BOT_LOGIN_WEBHOOK_TOKEN;
   const providedToken = req.body?.token;
@@ -53,22 +95,26 @@ app.post('/bot/messenger-login', async (req, res) => {
     return;
   }
 
-  const user = userId
-    ? await prisma.user.findUnique({ where: { id: userId } })
-    : await prisma.user.findFirst({
-        where: {
-          email: {
-            equals: email,
-            mode: 'insensitive',
-          },
-        },
-      });
+  const user = await resolveUserForMessenger({
+    userId,
+    email,
+  });
 
   if (!user) {
     res.status(404).json({ error: 'User not found.' });
     return;
   }
 
+  await prisma.messengerConnection.updateMany({
+    where: {
+      userId: user.id,
+      type: channel,
+      isActive: true,
+      NOT: { channelId },
+    },
+    data: { isActive: false },
+  });
+
   await prisma.messengerConnection.upsert({
     where: {
       userId_type_channelId: {