Unreliable company

Just want everyone to know that Sentech Industries is the most unreliable, dishonest company in Port Elizabeth. They have been taking product from us, an NPO, but since November refuses to pay and not sending back the product. Now, they sent us a 'proof of payment' and upon close inspection, it appears to be an old payment made that they are trying to send as a new one. They still owe us R5000+. Why i am upset is not the money but because they are a big company who ****s an NPO who takes care of the destitute. Shame on you Sentech