In 15.1, I'm trying to create a Dues Subscription and change the amount from Special Pricing.
In the code below, the balance is provided correctly to $525, but the Billing Amount does not get assigned. It remains 0.

The special price is a flat fee of $525 for a member_type of "AM"

I simplified this in code to not look up the special pricing. I was successful in looking the $525 correctly, but the AmountBilled just does not get populated in the billing tab - only the balance.

Any suggestions?

CSubscription renew = contact.NewSubscription("BASIC", true);
renew.AmountBilled = 525;
renew.Balance = 525;
contact.BillSingleNonDuesSubscription(rewew.Product_Code,DateTime.Today);
contact.Save();