Bangula Lingo Centre not paying transcribers

I am terribly disappointed in Bangula Lingo Centre. I requested to do part time transcribing work for them. They made one payment, after this I submitted 9 transcriptions, which I did after hours in order to meet deadlines. It has been two months after the date they promised to pay. I would just like to give out a warning to any other transcibers, who are interested in doing work for them, as well as any companies who will be using their services. I would not use a supplier if they do not pay the amount promised as per Invoice.