diff --git a/Models/ScannedKeyRecord.cs b/Models/ScannedKeyRecord.cs
index 38eaafd..6929425 100644
--- a/Models/ScannedKeyRecord.cs
+++ b/Models/ScannedKeyRecord.cs
@@ -15,5 +15,5 @@ public class ScannedKeyRecord
     public string ScannedAt { get; set; }        // Wann gefunden
     public string CheckedAt { get; set; }        // Wann zuletzt geprüft
     public int Deleted { get; set; }             // Soft-Delete (1 = gelöscht/ignoriert)
-    public long? AdoptedApiKeyId { get; set; }   // Verknüpfung zur api_keys.id (null = nicht übernommen)
+    public string AdoptedApiKeyId { get; set; }   // Verknüpfung zur api_keys.key_id (null = nicht übernommen)
 }
diff --git a/Services/DatabaseService.Integrations.cs b/Services/DatabaseService.Integrations.cs
index 83a82dd..47f2344 100644
--- a/Services/DatabaseService.Integrations.cs
+++ b/Services/DatabaseService.Integrations.cs
@@ -423,6 +423,14 @@ public partial class DatabaseService
     public async Task DeleteApiKey(string keyId)
     {
         using var conn = CreateConnection();
+        // Scanned-Keys die auf diesen API-Key verweisen zurücksetzen
+        await conn.ExecuteAsync(
+            "UPDATE scanned_keys SET adopted_api_key_id = NULL WHERE adopted_api_key_id = (SELECT id FROM api_keys WHERE key_id = @keyId)",
+            new { keyId });
+        // User die diesen Key ausgewählt haben zurücksetzen
+        await conn.ExecuteAsync(
+            "UPDATE users SET selected_api_key_id = NULL WHERE selected_api_key_id = @keyId",
+            new { keyId });
         await conn.ExecuteAsync("DELETE FROM api_keys WHERE key_id = @keyId", new { keyId });
     }