encountered some serious problems with my bicycle

When I was leaving Copacabana, I encountered some serious problems with my bicycle. I thought I will stay one more day in the town in order to fix these problems... Back in town, I met four Argentinian cyclists met a week before in La Paz, who were camping at the lake and working in the town. We spent a nice afternoon and evening. They helped me to fix my bicycle, but a new problem appeared as a screw supporting the rear rack broke down inside a bicycle part. I will try to fix it today and maybe wait until Monday to find some workshop that could help me...