Changing courses at uni... I don't know what to do

So I have just completed my first year of uni for the course politics, at the beginning of the year i attempted to change my course but was not taken seriously by my personal tutor, so I stayed on the course despite not liking it. Fast forward to now, I have applied to change courses to global sustainable development (GSD) and business studies as a joint honours degree. However. i have just been updated that the course is over subscribed and that they can offer me a place on the GSD course but I was not able to do the joint honours degree programme and their decision to is final. I'm stuck on what to do because I really wanted to do this joint honours degree. I was told that I would be able to do business modules as well but only if the Business department would allow me to do so, but my issue is that my degree title will not include the business studies portion, I know it doesn't seem like a big deal but it was important for me to have both. Im not sure what I should do. Help is much appreciated.