✅ what should I do to use derived class for return type?

public abstract class CommandResult
{
    public string Error { get; set; }
}

public abstract class CommandResult2 : CommandResult
{
    public string Error { get; set; }
    public string Data { get; set; }
}

public abstract class SolverManagerPureCommand<TArgument>
{
    protected abstract Task<CommandResult> ExecuteInternalCoreAsync(TArgument argument);
}

public sealed class BuildDataSetCommand : SolverManagerPureCommand<string>
{
    protected override Task<CommandResult> ExecuteInternalCoreAsync(string argument)
    {
        throw new NotImplementedException();
    }
}

public abstract class CommandResult
{
    public string Error { get; set; }
}

public abstract class CommandResult2 : CommandResult
{
    public string Error { get; set; }
    public string Data { get; set; }
}

public abstract class SolverManagerPureCommand<TArgument>
{
    protected abstract Task<CommandResult> ExecuteInternalCoreAsync(TArgument argument);
}

public sealed class BuildDataSetCommand : SolverManagerPureCommand<string>
{
    protected override Task<CommandResult> ExecuteInternalCoreAsync(string argument)
    {
        throw new NotImplementedException();
    }
}

protected override Task<CommandResult2> ExecuteInternalCoreAsync(string argument)

protected override Task<CommandResult2> ExecuteInternalCoreAsync(string argument)