Banks restricting depositing money to forex brokers

I have been trying to deposit money to my forex broker for days now and I am being declined. I tried with FNB and standard bank they both declined. It was a weekend so I couldn't get help from the card services. When I spoke to my forex friends they told me they having the same issue. Why would banks prevent us from forex trading yet they make money through us. This is not fair at all. I needed money to back my account up and I wasn't able to fund my broker until my account was blown out. I lost a lot of money because FNB and Standard bank couldn't allow me to fund my broker with my own money. How can they do this to us without even a warning. This is a career for some of us. We a earn a living through this. We demand an explanation as to what's going on, why are we unable to deposit money to our brokers some cannot even withdraw to their cards. This is extremely frustrating and extremely inconveniening. Can you explain why you failing us like this yet we paying for services every month which we not even getting.