Quando executei o comando o console retornou esses erros.
PM> Add-Migration unidade System.Reflection.TargetInvocationException: Uma exce�ao foi acionada pelo destino de uma chamada. ---> System.TypeLoadException: Nao foi poss�vel carregar o tipo Microsoft.EntityFrameworkCore.Internal.LazyRef`1 do assembly Microsoft.EntityFrameworkCore, Version=3.1.6.0, Culture=neutral, PublicKeyToken=adb9793829ddae60. em Microsoft.EntityFrameworkCore.Design.OperationExecutor..ctor(Object reportHandler, IDictionary args) --- Fim do rastreamento de pilha de exce�oes internas --- em System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor) em System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) em System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, StackCrawlMark& stackMark) em System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) em System.Activator.CreateInstance(String assemblyString, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, Evidence securityInfo, StackCrawlMark& stackMark) em System.Activator.CreateInstance(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) em System.AppDomain.CreateInstance(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) em System.AppDomain.CreateInstanceAndUnwrap(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) em System.AppDomain.CreateInstanceAndUnwrap(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) em Microsoft.EntityFrameworkCore.Tools.AppDomainOperationExecutor..ctor(String assembly, String startupAssembly, String projectDir, String contentRootPath, String dataDirectory, String rootNamespace, String environment) em Microsoft.EntityFrameworkCore.Tools.Commands.ProjectCommandBase.CreateExecutor() em Microsoft.EntityFrameworkCore.Tools.Commands.MigrationsAddCommand.Execute() em Microsoft.DotNet.Cli.CommandLine.CommandLineApplication.Execute(String[] args) em Microsoft.EntityFrameworkCore.Tools.Program.Main(String[] args) Uma exce�ao foi acionada pelo destino de uma chamada.
Se puderem me ajudar ficarei agredecido
