Inconsistent Vodacom wants to boot loyal customers...

I have been a customer of Vodacom since 2006 (13 years). I currently have 3 contracts of which I am due for a upgrade on number ********** 660. I approached a Vodashop and app**** for an upgrade. I am currently on a UChoose Flexi 200 contract with a BlackBerry KeyOne phone costing me R429.00 per month. I chose the CatS31 on contract for R389pm. I was informed this morning that I cannot upgrade due to a bad reflection on my creditburo report. The point I want to make is that I have been under debt review since 2017 and have upgraded during September 2017 on number ********** 660, November 2017 on number ********** 894 and March 2018 on number ********** 376 of which my debt review HAS NEVER had an effect on my upgrade. Afterall my account is paid up and is not in arrears. Furthermore I am currently upgrading to a package that will cost me R389pm and no longer R429pm and I am declined an upgrade except if I pay in a once-off payment fee of R3000??? Why has Vodacom assisted me in the past while being under debt review and now refusing me to upgrade? Afterall I am doing an upgrade and not applying for a new contract? I have always been a loyal customer of Vodacom yet if feels like they are now giving me the boot although Vodacom is not being consistent as they helped me in the past while I was under debt review too??