diff --git a/Security/Services/PreAuthService.cs b/Security/Services/PreAuthService.cs
index 21c97ff..484c5a1 100644
--- a/Security/Services/PreAuthService.cs
+++ b/Security/Services/PreAuthService.cs
@@ -16,7 +16,7 @@ public class PreAuthService(ICacheService cache)
     private static string GeneratePreAuthToken() => Guid.NewGuid().ToString().Replace("-", "") + 
                                                       GeneratorKey.GenerateString(16);
 
-    public async Task<PreAuthTokenResponse> CreateLoginTokenAsync(TokenRequest request, string userId, CancellationToken cancellation = default)
+    private static string GetPreAuthCacheKey(string fingerprint) => $"{fingerprint}_pre_auth_token";
     {
         var firstAuthToken = GenerateFirstAuthToken();
 
@@ -29,7 +29,7 @@ public class PreAuthService(ICacheService cache)
         };
 
         await cache.SetAsync(
-            request.Fingerprint,
+            GetPreAuthCacheKey(request.Fingerprint),
             JsonSerializer.SerializeToUtf8Bytes(loginStructure),
             Lifetime,
             cancellation);