Listen Clear Non payment for lead services Savannah Georgia

I delivered qualified leads to Listen Clear and Listen Clear has been telling me for 3 months that they will pay my invoice and now they tell me that the leads were not qualified.  Why would they send me daily reports of the qualified leads and tell me that they will pay me if the leads were not qualified?  My invoice is based on THEIR reporting not mine which means I billed them on the leads that THEY told me were qualified.  They have a reputation for not paying their lead vendors and it seems that I am the latest victim of their unethical business practices.  This company needs to be accountable for their actions, they cannot decide who and when to pay after services have been rendered to them.  They cannot string businesses along for months telling them that they will pay them and then randomnly decide not to pay them.  They accepted the leads and they need to pay the leads.  I have several emails from Listen Clear telling me that they will pay me and that they're sorry for the delay.  Again, why would they acknowledge and agree to pay me if the leads were not qualified, makes no sense.  They are putting people at harm by using these unethical business practices.