Account allocations

I have a number of accounts with Sage Pastel online Accounting. Each account is a separate entity. I am up to date with payments but the payments are not being allocated to the correct entity. I have phoned numerous times where they admit the mistake but do not rectify it or promise to phone back. This does not happen. This has being going on for 9 months. I hate their call centre as they take forever to answer. I was once on hold for 90 minutes before being answered.