Master Studies, Bielefeld Germany

I saved up over 10000 euro to come and study here in Germany. 8640 EURO is one of the conditions to come and be able to live here. I am currently living on my saved up money but I was shocked when the city told me that I need the same amount of money to be able to renew my residency card and legally live here next year. So I felt maybe all the money I spent would be wasted and I will be going back before even starting my master. They also told me that I can not work in the first year. I am going to study my master next winter semester after finishing the language.