Customers not making the effort to pay for services rendered

Good day. We do google online advertising and marketing. This involves the client sending us pictures and logos for the advert. Once approved it gets published online. This client has signed legal binding documents for furtherance of work. We have also covered him on social media as well as GPS. Mr Thato Makheka has completed ignored all our calls from March this year and has made several promises to pay but has not made a single payment yet. The whole world is in this pandemic but if people pay their dues or make suitable arrangements, we can all live. This is not a regular individual but an owner of a business without the care to make contact and worse still ignoring all attorney calls as well as calls from the agent