diff --git a/csharp/App/Backend/Database/User.cs b/csharp/App/Backend/Database/User.cs
index e002c48be..77897bffd 100644
--- a/csharp/App/Backend/Database/User.cs
+++ b/csharp/App/Backend/Database/User.cs
@@ -1,6 +1,9 @@
+using System.Diagnostics.CodeAnalysis;
 using System.Net.Mail;
 using System.Security.Cryptography;
 using System.Text;
+using System.Text.Json;
+using System.Text.Json.Nodes;
 using Flurl.Http;
 using Innovenergy.Backend.Model;
 using Innovenergy.Backend.Utils;
@@ -56,38 +59,41 @@ public partial class Db
         return Create(user);
     }
 
+    [UnconditionalSuppressMessage("Trimming", "IL2026:Members annotated with 'RequiresUnreferencedCodeAttribute' require dynamic access otherwise can break functionality when trimming application code", Justification = "<Pending>")]
     public Object CreateAndSaveUserS3ApiKey(User user)
     {
         //EXOSCALE API URL
         const String url = "https://api-ch-dk-2.exoscale.com/v2/access-key";
         const String secret = "S2K1okphiCSNK4mzqr4swguFzngWAMb1OoSlZsJa9F0";
         const String apiKey = "EXOb98ec9008e3ec16e19d7b593";
-        var payload = new
-        {
-            name = user.Email,
-            operations = new List<String> { "getObject", "listBucket" },
-            content = new List<Object> { }
-        };
 
-        var installationIdList = User2Installation
+        var installationList = User2Installation
             .Where(i => i.UserId == user.Id)
             .SelectMany(i => Installations.Where(f => i.InstallationId == f.Id))
             .ToList();
 
-        foreach (var installation in installationIdList)
+       
+        var instList = new JsonArray();
+        
+        foreach (var installation in installationList)
         {
-            payload.content.Add(new { domain = "sos", resource_type = "bucket", resource_name = installation.Name }); //TODO CHANGE NAME TO S3BUCKET
+            instList.Add(new JsonObject {["domain"] = "sos",["resource-name"] = installation.Name,["resource-type"] = "bucket"});
         }
-
+        
+        var jsonPayload = new JsonObject { ["name"] = user.Email, ["operations"] = new JsonArray{ "getObject", "listBucket" }, ["content"] = instList};
+        var expiration = DateTime.Now.AddHours(24);
+        
+        var signature = $"POST /v2/access-key\n{jsonPayload}\n\n\n{expiration}";
         using var hmacSha1 = new HMACSHA1(Encoding.UTF8.GetBytes(secret));
-        var signature = Encoding.UTF8
-            .GetBytes(payload.ToString())
+        
+        signature = Encoding.UTF8
+            .GetBytes(signature)
             .Apply(hmacSha1.ComputeHash)
             .Apply(Convert.ToBase64String);
 
         var keyJson = url
-            .WithHeader("Authorization", $"POST {apiKey};{signature}")
-            .PostJsonAsync(payload)
+            .WithHeader("Authorization", $"EXO2-HMAC-SHA256 credential={apiKey},expires={((DateTimeOffset)expiration).ToUnixTimeSeconds()},signature={signature}")
+            .PostJsonAsync(jsonPayload.ToString())
             .ReceiveJson()
             .Result;
 
diff --git a/csharp/App/Backend/db.sqlite b/csharp/App/Backend/db.sqlite
index 982a3ab91..ce3c81c14 100644
Binary files a/csharp/App/Backend/db.sqlite and b/csharp/App/Backend/db.sqlite differ