appealing against housing

Other

I have a tenant who is currently nearly three months in rent arrears. Her rent is paid by housing benefit. I have informed housing and have completed the forms for housing to now be paid direct to myself. The tenant has also asked for them to pay me direct. However, they sent me a letter today saying that they have made a decision to pay the tenant direct. Her previous landlady has also informed them that she had rent arrears there. What can I do about this and where do I legally stand with housing. Thanks