Arrangements done, still they phone and tell no arrangements in place

Hi, Customer Service, after arrangements was done via telephone call, and email for payments, they phone and tell no arrangements is in place and need to make new arrangements. Please advise, why is this happening? The payments are done as arrange. What happened to emails send and the phone calls to make arrangements, the account is paid according to the arrangement. After years of having the account, it is disappointed how the account is handled.