Cannot add coupon to cart


I am still facing this issue ( right now (cannot add coupon to cart using the API). After calling the endpoint, the cart shows no coupon.
I use Shopping Cart Module version 3.10.0.

Could you provide more details?

  1. Marketing promotion details. Maybe coupon could not be applied for this reason
  2. API Request/response which can help to repeat the problem (for example Fiddler or Postman sessions).