Refactoring if else

partial void OnNameChanging(string value)
        {
            _validationService.ClearErrors(nameof(Name));
            ErrorsList.ToList()
                      .Where(error => error.PropId == 1)
                      .All(error => ErrorsList.Remove(error));

            if (string.IsNullOrEmpty(value) || string.IsNullOrWhiteSpace(value))
            {
                _validationService.AddError(nameof(Name), "You must provide your pet a name");

                var errors = GetErrors(nameof(Name)).OfType<string>().ToList();
                errors.ForEach(error => ErrorsList.Add(new ValidationProperty(1, error)));

            }
            else if (value.Length < 3)
            {
                _validationService.AddError(nameof(Name), "Your pet name is a little short");

                var errors = GetErrors(nameof(Name)).OfType<string>().ToList();
                errors.ForEach(error => ErrorsList.Add(new ValidationProperty(1, error)));
            }
            else if (value == "Snow")
            {
                _validationService.AddError(nameof(Name), "Wait! ain't snow is already in your profile ?");

                var errors = GetErrors(nameof(Name)).OfType<string>().ToList();
                errors.ForEach(error => ErrorsList.Add(new ValidationProperty(1, error)));
            }
        }

Console.WriteLine(GetErrorMessage(""));
Console.WriteLine(GetErrorMessage("\t"));
Console.WriteLine(GetErrorMessage(null));
Console.WriteLine(GetErrorMessage("test"));
Console.WriteLine(GetErrorMessage("as"));
Console.WriteLine(GetErrorMessage("Snow"));

string? GetErrorMessage(string? value)
{
    //_validationService.ClearErrors(nameof(Name));
    //ErrorsList.ToList()
    //          .Where(error => error.PropId == 1)
    //          .All(error => ErrorsList.Remove(error));

    string? errorMessage = value switch
    {
        _ when string.IsNullOrWhiteSpace(value) => "You must provide your pet a name",
        _ when value.Length < 3 => "Your pet name is a little short",
        "Snow" => "Wait! ain't snow is already in your profile ?",
        _ => null
    };

    //if (errorMessage is not null)
    //{
    //    _validationService.AddError(nameof(Name), errorMessage);

    //    var errors = GetErrors(nameof(Name)).OfType<string>().ToList();
    //    errors.ForEach(error => ErrorsList.Add(new ValidationProperty(1, error)));
    //}

    return errorMessage;
}