If your total consumption in the current period is 15, yuan, I suggest that you can apply for the bill installment of CCB. Installment of bills means to apply to CCB for installment of the billed consumption amount from the billing date to the final repayment date (only once every 3 days). However, the maximum application amount does not exceed 9% of the total consumption amount in the issued bill (excluding cash withdrawal, installment payment and other transactions stipulated by CCB), which is for the whole bill application. Moreover, there is a fee concession for the installment of CCB's bills, so I will calculate it for you at the preferential rate.
If your installment quota is sufficient (the installment quota is set at 1% of your credit card's permanent quota), then the maximum installment amount that can be applied for the current consumption is 15, * .9 = 13,5, and the principal of each installment is 13,5/12 = 1125. The handling fee for each period is 135*.54%=72.9, the total handling fee for the 12th period is 72.9*12=874.8, and the installment amount recorded for each period in the future is 1125+72.9=1197.9.