Sustainable Collections Services should be struck off in terms of in terms of the Debt Collectors Act

This collection agency is a disgrace - they send countless threats on behalf of Lancet Laboratories threatening to adversely list my credit rating despite my regular advise to them to get Lancet to charge their fees to Discovery who have paid countless of their fees on my behalf in the past. I am tired of their malicious threats and failure to deal with my request to stop harassing me and get Lancet to charge Discovery with the right codes with which they will be paid