FALSE ADVERTISING

I bought a Note 4 handset, where MTN is advertising that you get a cover valued at R400 for free when you buy it in the month of Feb.Upon inquiring from the consultant I was told the store will only get the covers in March of which I will not be eligible for it in March as i have bought it in February...My question is why advertise something as a February special if you know you'll only have stock of it in March, And what is most frustrating is that no one is willing to help and make me understand this, I am just being sent from Pillar to Post.