Bad Payers !!

Being new in the transport business, these people was our first clients. We delivered a load of charcoal at their property on the 16th of March 2015, being that the norm for them was that we deliver the load first and then they pay and the fact this was the 3rd time we did business with them without any previous problems. After the delivery was made, we noticed that our phone calls were not being answered. We decided to get our local debt collectors on the case after weeks went by without them answering calls or emails or even whatsapps. They eventually started answering when they needed another load delivered, I then said that we will deliver only once I receive the previous payment. needless to say, I haven't heard from them since.