I have been a XXXX cellular customer for over XXXX years until the year of XXXX. XXXX promise there customers that for an upgrade fee and renewal of the cellular contract, the customers will be getting XXXX cellular service. I renewed my contract thinking I was going to get faster cellular and internet service. This offer was back in the XXXX. After I accepted this offer I did not get XXXX service, instead I got slow connections and a lot of missed and dropped cellular calls. This went on for months and XXXX did not deliver as promise. After I contacted XXXX and tried to get an explanation, I got a lot of apologies and no result or change of service as promised. I then contacted them and told them that the lack of their promised service which I was paying for was a breach of contract and I was not getting service as indicated in the cellular service contract. I then spoke to someone in sprint and they apologized for this inconvenience and I ended my contract and switched to XXXX cellular service. After a few months with XXXX, I received a collection notice from XXXX advising that I owe them money for breaking contract. I thought to my self wow after they did not deliver service as agreed on their contract they want me to pay after I spoke to them and they agreed that they were not delivering the service as promised because of some issued they have with a XXXX contractor. This is an unfair business practice and I immediately contacted the XXXX, XXXX and XXXX to notify them of this issue. This was back in XXXX. After the investigation was made against XXXX collection department ( Diversified Consultants ) they found that it was not accurate and deleted them off my credit file. Now this year on the month of XXXX, XXXX re-reported the collection as if it was a new debt using Diversified Consultants to XXXX, XXXX and XXXX. I then sent XXXX, XXXX and XXXX a letter notifying them that this was a duplicate collection and that the contract was legally broken and I did not owe then any money. Well unfortunately this time XXXX, XXXX and XXXX refused to delete the information and wo n't recognize this as an invalid debt even when it is an invalid debt. Please help me to resolve this issue and stop this unfair practice.