diff --git a/WebApi/Authentication/CurrentUser.cs b/WebApi/Authentication/CurrentUser.cs
index f2921b6..cedf335 100644
--- a/WebApi/Authentication/CurrentUser.cs
+++ b/WebApi/Authentication/CurrentUser.cs
@@ -12,7 +12,7 @@ public sealed class CurrentUser : IBindableFromHttpContext<CurrentUser>
         IsAuthenticated = isAuthenticated.HasValue && isAuthenticated.Value;
 
         var rawId = principal.FindFirstValue(ClaimTypes.NameIdentifier);
-        if (Guid.TryParse(rawId, out var id) && id != Guid.Empty)
+        if (long.TryParse(rawId, out var id) && id != 0)
             Id = id;
 
         Username = principal.FindFirstValue(ClaimTypes.Name);
@@ -24,7 +24,7 @@ public sealed class CurrentUser : IBindableFromHttpContext<CurrentUser>
 
     public bool IsAuthenticated { get; }
 
-    public Guid? Id { get; }
+    public long? Id { get; }
 
     public string? Username { get; }
 
@@ -32,7 +32,7 @@ public sealed class CurrentUser : IBindableFromHttpContext<CurrentUser>
 
     public string? LastName { get; }
 
-    public Guid RequiredId => Id ?? throw new InvalidOperationException("User Id claim is missing or invalid.");
+    public long RequiredId => Id ?? throw new InvalidOperationException("User Id claim is missing or invalid.");
 
     public bool HasClaim(string type) => Principal.HasClaim(c => c.Type == type);
 
diff --git a/WebApi/Authentication/JwtBearerEventsHandler.cs b/WebApi/Authentication/JwtBearerEventsHandler.cs
index 4819d10..5891465 100644
--- a/WebApi/Authentication/JwtBearerEventsHandler.cs
+++ b/WebApi/Authentication/JwtBearerEventsHandler.cs
@@ -5,21 +5,49 @@ using System.Security.Claims;
 
 namespace WebApi.Authentication;
 
-public sealed class JwtBearerEventsHandler(IMediator mediator) : JwtBearerEvents
+public sealed class JwtBearerEventsHandler(IMediator mediator, ILogger<JwtBearerEventsHandler> logger) : JwtBearerEvents
 {
     public override async Task TokenValidated(TokenValidatedContext tokenValidatedContext)
     {
         var principal = tokenValidatedContext.Principal!;
 
-        var id = principal.FindFirstValue(ClaimTypes.NameIdentifier)!;
-        var guidId = Guid.Parse(id);
+        var rawId = principal.FindFirstValue(ClaimTypes.NameIdentifier);
+        if (!long.TryParse(rawId, out var userId))
+        {
+            logger.LogWarning("Token subject '{Subject}' is not a numeric id; skipping user provisioning", rawId);
+            return;
+        }
+
+        var username = principal.FindFirstValue(ClaimTypes.Name)
+            ?? principal.FindFirstValue("preferred_username")
+            ?? principal.FindFirstValue(ClaimTypes.Email)
+            ?? rawId!;
 
-        var username = principal.FindFirstValue(ClaimTypes.Name)!;
         var firstName = principal.FindFirstValue(ClaimTypes.GivenName);
         var lastName = principal.FindFirstValue(ClaimTypes.Surname);
 
-        await mediator.Send(
-            new CreateUserCommand(guidId, username, firstName, lastName),
-            tokenValidatedContext.HttpContext.RequestAborted);
+        try
+        {
+            await mediator.Send(
+                new CreateUserCommand(userId, username, firstName, lastName),
+                tokenValidatedContext.HttpContext.RequestAborted);
+        }
+        catch (Exception exception)
+        {
+            logger.LogError(exception, "Failed to provision user {UserId} during token validation", userId);
+        }
+    }
+
+    public override Task AuthenticationFailed(AuthenticationFailedContext context)
+    {
+        logger.LogWarning(context.Exception, "JWT authentication failed");
+        return Task.CompletedTask;
+    }
+
+    public override Task Challenge(JwtBearerChallengeContext context)
+    {
+        if (context.AuthenticateFailure is not null)
+            logger.LogWarning("JWT challenge: {Error} - {Description}", context.Error, context.ErrorDescription);
+        return Task.CompletedTask;
     }
 }
diff --git a/WebApi/DataTransferObjects/Users/CreateUserRequest.cs b/WebApi/DataTransferObjects/Users/CreateUserRequest.cs
index 5937975..24c7442 100644
--- a/WebApi/DataTransferObjects/Users/CreateUserRequest.cs
+++ b/WebApi/DataTransferObjects/Users/CreateUserRequest.cs
@@ -1,7 +1,7 @@
 namespace WebApi.DataTransferObjects.Users;
 
 public record CreateUserRequest(
-    Guid Id,
+    long Id,
     string Name,
     string? FirstName,
     string? SecondName);
diff --git a/WebApi/Endpoints/PlayListEndpoints.cs b/WebApi/Endpoints/PlayListEndpoints.cs
index e2a0b0f..36ca9d9 100644
--- a/WebApi/Endpoints/PlayListEndpoints.cs
+++ b/WebApi/Endpoints/PlayListEndpoints.cs
@@ -74,7 +74,7 @@ public static class PlayListEndpoints
 
     private static async Task<IResult> GetPlayListsByUserId(
         IMediator mediator,
-        Guid userId,
+        long userId,
         CancellationToken cancellationToken,
         string? name,
         int pageNumber = 1,
diff --git a/WebApi/Endpoints/TrackEndpoints.cs b/WebApi/Endpoints/TrackEndpoints.cs
index 4cd9839..44ad9dc 100644
--- a/WebApi/Endpoints/TrackEndpoints.cs
+++ b/WebApi/Endpoints/TrackEndpoints.cs
@@ -83,7 +83,7 @@ public static class TrackEndpoints
 
     private static async Task<IResult> GetTracksByUserId(
         IMediator mediator,
-        Guid userId,
+        long userId,
         CancellationToken cancellationToken,
         string? name,
         int pageNumber = 1,
diff --git a/WebApi/Endpoints/UserEndpoints.cs b/WebApi/Endpoints/UserEndpoints.cs
index 63bb430..c966c89 100644
--- a/WebApi/Endpoints/UserEndpoints.cs
+++ b/WebApi/Endpoints/UserEndpoints.cs
@@ -43,7 +43,7 @@ public static class UserEndpoints
 
     private static async Task<IResult> GetUserById(
         IMediator mediator,
-        Guid id,
+        long id,
         CancellationToken cancellationToken)
     {
         var result = await mediator.Send(new GetUserByIdQuery(id), cancellationToken);
diff --git a/WebApi/Scalar/ScalarOptionsSetup.cs b/WebApi/Scalar/ScalarOptionsSetup.cs
index b78ca39..add12dc 100644
--- a/WebApi/Scalar/ScalarOptionsSetup.cs
+++ b/WebApi/Scalar/ScalarOptionsSetup.cs
@@ -25,6 +25,7 @@ public sealed class ScalarOptionsSetup(IOptions<AuthenticationConfiguration> opt
                 flow.Pkce = Pkce.Sha256;
                 flow.SelectedScopes = _configuration.Scopes;
                 flow.RedirectUri = _configuration.ScalarRedirectUri;
+                flow.RefreshUrl = _configuration.TokenEndpoint;
             } )
             .HideModels();
     }