Since you promised to send a gift but didn't send it, you can communicate with the merchant. If the communication fails, they can complain to the regulatory authorities and produce enough evidence to prove their false propaganda, then they will be punished.

Of course, the supervision departments of different shopping channels are different. Online shopping is to find the customer service of the platform. For example, a treasure looks for Tao Xiaoer, and an east looks for their customer service phone number.

Relatively speaking, businesses will respond positively when they receive complaints, so don't worry too much.