Plugin 4.3 to 4.4 : Error while validating the service descriptor 'ServiceType'

When trying to upgrade a plugin from 4.3 to 4.4 I am getting:

AggregateException: Some services are not able to be constructed (Error while validating the service descriptor 'ServiceType: nopCommerce.Pro.Baldar.Controllers.BaldarController Lifetime: Transient ImplementationType: nopCommerce.Pro.Baldar.Controllers.BaldarController': Unable to resolve service for type 'nopCommerce.Pro.Baldar.Services.IBaldarService' while attempting to activate 'nopCommerce.Pro.Baldar.Controllers.BaldarController'.)

Any suggestiongs?

RE: eyalankri wrote:
Is that your service ?
If so have you registered the service in DependencyRegistrar
            services.AddScoped<IMyService, MyService>();

I had a mistake there. thank you.