Business cellphone upgrade

I have had a business account with Vodacom for at least 15 years . I have had my current phone , a Samsung Galaxy J1 for about 3 years . When i tried to upgrade my phone , i was informed that we are not due for an upgrade until November 2019 , that means that my current phone will be nearly 4 years old & it is already giving me trouble . I have spoken to 3 consultants , who promise to look into the problem & get back to me , clearly they haven't ?? Who in their right minds doesn't upgrade to a new phone when it is due ? Really unacceptable !!!!