JSON , разбор кода

есть вот такой запрос в Json формате :

{"resultCode":"OK","payload":[ {"name":",blabla","hidden":false,"accounts":[{"rate":0.0,"name":"blablaaALLAirlines","cardNumbers": [{"pinSet":true,"statusCode":"NORM","name":"AllAirLines","activated":true,"iconType":"ALLAIRLINES","expirationStatus":"normal","availableBalance":{"currency":{"code":643,"name":"RUB"},"value":-2414.3000},"reissued":false,"status":"blaaa","position":1,"value":"521324******0001","primary":true}], "currentRecommendedPayment":{"currency":{"code":643,"name":"RUB"},"value":2000.0000},"totalExpense":{"currency":{"code":643,"name":"RUB"},"value":0.0000},"totalIncome":{"currency":{"code":643,"name":"RUB"},"value":0.0000},"duedate":{"milliseconds":1491609600000},"creditLimit":{"currency":{"code":643,"name":"RUB"},"value":50000.0000},"hidden":false,"accountIconType":"ALLAIRLINES","lastPaymentDate":{"milliseconds":1488812773000},"currentMinimalPayment":{"currency":{"code":643,"name":"RUB"},"value":2000.0000},"status":"NORM","moneyAmount":{"currency":{"code":643,"name":"RUB"},"value":0.0000},"accountType":"Credit","position":3,"accountGroup":"blabla"}]}]} 

Код отвечает за логику формирования общей задолженности на кредитной карте, указана 50000 ( атрибут “creditLimit” ), однако по факту задолженность больше, подскажите в чем здесь ошибка и какая должна быть правильная логика формирования общей задолженности ?