getRewardsBalance
fun getRewardsBalance(nonce: String, currencyIsoCode: String, callback: AmericanExpressGetRewardsBalanceCallback)
Gets the rewards balance associated with a Braintree nonce. Only for American Express cards.
Parameters
nonce
A nonce representing a card that will be used to look up the rewards balance
currencyIsoCode
The currencyIsoCode to use. Example: 'USD'