public void SetDefault(string userName, string defaultPaymentMethodId)
{
var paymentMethods = _paymentMethodsDictionary[userName];
//Clear old default payment methods
var oldDefaults = paymentMethods.Where(a => a.IsDefault);
foreach (var oldDefault in oldDefaults)
{
oldDefault.IsDefault = false;
}
var defaultPaymentMethod = paymentMethods.Find(a => a.Id == defaultPaymentMethodId);
if (defaultPaymentMethod != null)
{
defaultPaymentMethod.IsDefault = true;
}
}