Cannot create tenant with admin user #1503

Hello, I have some periodical service, which is synchronizing tenants. To do that, of course, I have to use a method from TenantManager.cs which is named CreateWithAdminUserAsync

I'm calling this method from my custom manager and it fails during the <ins>second</ins>time tenant is created. I suppose this is something connected with

using (var uow = _unitOfWorkManager.Begin(TransactionScopeOption.RequiresNew))

but I'm not sure. It fails on DbContext.Save with timeout exception.

Here is a stack trace:

at System.Data.Entity.Core.Mapping.Update.Internal.UpdateTranslator.<UpdateAsync>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Core.Objects.ObjectContext.<ExecuteInTransactionAsync>d__3d`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Core.Objects.ObjectContext.&lt;SaveChangesToStoreAsync&gt;d__39.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.&lt;ExecuteAsyncImplementation&gt;d__9`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Core.Objects.ObjectContext.<SaveChangesInternalAsync>d__31.MoveNext()

First time I'm creating tenant - success. By the second iteration of cycle is failing with exception of timeout. Also I have tried to set UnitOfWork(IsDisabled = true) like it is in the TenantAppService, but this didn't help me.

Does anybody know the reason of this problem?