This will be due to the Evo contracts @Fatsxxboy . When you take out a device plan you will need to agree to a new airtime plan and need to be out of your previous contract or pay an upgrade charge.
The benefit of an Evo plan is if you are able to pay off the device plan part of the contract, you will be released from the airtime contract and this will carry on as 30 days until you cancel or take out a new device plan. The one thing to consider is the device plan is a credit agreement and you will be hard credit checked each and every time you take out a new device plan.
If you contact sales, they will be able to help. There is further information here: Evo
