Upgrade not allowed

This is my second complaint this week, I am due for an upgrade and was told that they cannot assist me because of my credit score on itc??? I have three contracts with Vodacom, have been a client for 10+ years, my account is R1200 per month paid promptly, and this does not count for anyhting??? I lost my job two years ago, which caused me to fall behind with other accounts which I am paying off, thus some itc listings. But even through this time my Vodacom account was always paid. I am really disgusted and disappointed to say the least. My current phone is already broken and now I cannot even upgrade.