Poor treatment of tenants

Good morning, I hope you are well. I have a query that I would like to address, I am a tenant of afcho properties, and I have been in one of their properties for just over 12 months now, they have been sending communication that on your 7th month you will get 25% discount on your rent, but I have never gotten a discount so today I sent an email to them asking about the discount, only today they tell me that the mail was sent by error and it only applies to tenants in the inner city of Johannesburg. I am very frustrated because it's not the first time something like this happened, and our rent was also increased without any communication, I need advice from anyone to assist because this is no way to treat a tenant.