Upgrade not available. Profile too low nonsense.

My cellphone contract is due for an upgrade, and when I tried to upgrade to get the SONY XPERIA Z3 Compact TAB, the consultant told me that my portfolio is too low, so I can't upgrade. Even though I am almost at the end of a contract that is more expensive than the option I am now applying for? She then told me to request to the acquisitions department to increase my portfolio which was rejected. A couple days later I contacted an agent through the online portal, and the I was told again that my profile is too low. After being shunted around from department to agent, I still have no idea what to do? My account isn't behind or no payments have been missed, but now I am unable to upgrade. I'm going to cancel my contract as soon as it expires. This is UNACCEPTABLE!