When a promotion is restricted to a specific quantity of credit card installments (for example, "10% cash"), the discounted amount is applied even for installments out of the limited range, where the "installmentOptions" object from the orderForm API will return wrong values.

Selecting a different number of installments will recalculate promotions and refresh the values from all installments. You can't create an order with the wrong discount since it'll always be updated to the selected number of installments, so this issue is related only to the exhibited values.

• Create a promotion with a restricted amount of installments;
• Through the API, create or simulate a cart informing a "paymentData" with the number of installments in which the promotion is applied;
• Observe the "installmentOptions" about the discounted values;
• Inform another number of installments and see the value being refreshed to all of them.

This object has a limited behavior and should be considered obsolete.

Stores that depend on discounts for specific installments in an orderForm should be based on a new API, as described in this changelog (1) and this documentation (2).

This new API doesn't cover simulation requests. For them, the alternative is the "paymentSystemToCheckFirstInstallment" configuration (3) – but limited to discounts in the first installment.

(1) https://developers.vtex.com/vtex-developer-docs/changelog/improvement-price-consistency-checkout-discounts-installments

(2) https://developers.vtex.com/vtex-rest-api/reference/getcartinstallments

(3) https://developers.vtex.com/vtex-rest-api/docs/using-checkout-api-to-set-a-discount