ORA-01408: such column list already indexed

[DarioN1]

I'm trying to set up Hangfire with FluentNHibernate for on Oracle database, but I'm encountering the following error:

ORA-01408: such column list already indexed

I have the following setup:

RegisterHangfire.cs
public static void RegisterHangfire(
            this IServiceCollection serviceCollection,
            CustomSettings customSettings)
        {
            var storage = FluentNHibernateStorageFactory.For(
                ProviderTypeEnum.OracleClient10Managed,
                DATABASE_URL,
                new FluentNHibernateStorageOptions
                {
                    TransactionIsolationLevel = IsolationLevel.Serializable,
                    QueuePollInterval = TimeSpan.FromSeconds(15),
                    JobExpirationCheckInterval = TimeSpan.FromHours(1),
                    CountersAggregateInterval = TimeSpan.FromMinutes(5),
                    UpdateSchema = true,
                    DashboardJobListLimit = 50000,
                    InvisibilityTimeout = TimeSpan.FromMinutes(15),
                    TransactionTimeout = TimeSpan.FromMinutes(1),
                    JobQueueDistributedLockTimeout = TimeSpan.FromMinutes(1.0),
                    DistributedLockPollInterval = TimeSpan.FromSeconds(15.0),
                    DeadlockRetryInterval = TimeSpan.FromSeconds(1.0),
                    DbmsTimeSyncInterval = TimeSpan.FromMinutes(5.0),
                    TablePrefix = "HANGFIRE_",
                });

            serviceCollection.AddHangfire(cfg => cfg.UseStorage(storage));

            serviceCollection.AddHangfireServer();
        }
Program.cs

...

builder.Services.RegisterHangfire(customSettings);

var app = builder.Build();

app.UseHangfireDashboard();

...

I've tried changing the UpdateSchema property. It's strange that if I run with true the tables are created but the app throws an error: "ORA-01408: such column list already indexed" as if trying to recreated and reindex at every run. And when I change it to false it runs ok.

Should I determine if the tables are created in order to toggle the UpdateSchema property? Or I've configured the service wrong?

OracleDB is 19.17.0.0

.NET: 7

Nuggets:

• Hangfire: 1.8.5
• Hangfire.Core: 1.8.5
• Hangfire.FluentNHibernateStorage: 1.7.30
• Hangfire.Oracle.Core: 1.2.17
• FluentNHibernate: 3.3.0