diff --git a/apps/rebreak-native/app/(app)/blocker.tsx b/apps/rebreak-native/app/(app)/blocker.tsx
index 8b87b23..ef80161 100644
--- a/apps/rebreak-native/app/(app)/blocker.tsx
+++ b/apps/rebreak-native/app/(app)/blocker.tsx
@@ -61,7 +61,7 @@ export default function BlockerScreen() {
   }, [refreshDomains, syncBlocklist, refresh]);
   useDomainSubmissionRealtime(onDomainChange, true);
 
-  const [mailOpen, setMailOpen] = useState(true);
+  const [mailOpen, setMailOpen] = useState(false);
 
   // AddSheet state: tracks which section opened it
   const [addSheetOpen, setAddSheetOpen] = useState(false);
diff --git a/backend/server/api/custom-domains/index.post.ts b/backend/server/api/custom-domains/index.post.ts
index 13f42aa..94538be 100644
--- a/backend/server/api/custom-domains/index.post.ts
+++ b/backend/server/api/custom-domains/index.post.ts
@@ -7,6 +7,7 @@ import {
 } from "../../db/domains";
 import { getProfile } from "../../db/profile";
 import { getPlanLimits } from "../../utils/plan-features";
+import { usePrisma } from "../../utils/prisma";
 
 // Regex: Domain muss mindestens eine TLD haben (z.B. "casino.de", "x.co.uk")
 const DOMAIN_RE = /^[a-z0-9]([a-z0-9-]*[a-z0-9])?(\.[a-z0-9]([a-z0-9-]*[a-z0-9])?)+$/;
@@ -128,6 +129,20 @@ export default defineEventHandler(async (event) => {
     });
   }
 
+  // Pre-check: domain already on the global blocklist? Don't burn a slot for
+  // something the 208k-domain global filter already covers. Return 200 with a
+  // flag so the frontend can surface "already protected, no slot needed"
+  // without the user paying for it. mail_domain is included in the same check
+  // because mail-domains land in the same blocklist set the daemon scans.
+  const db = usePrisma();
+  const globalMatch = await db.blocklistDomain.findFirst({
+    where: { domain: value, isActive: true },
+    select: { domain: true },
+  });
+  if (globalMatch) {
+    return { alreadyGlobal: true, domain: value };
+  }
+
   // Per-type Slot-Limit prüfen
   const profile = await getProfile(user.id);
   const limits = getPlanLimits(profile?.plan ?? "free");