Radio Error Code

Before I ask the question; I tried to make a small donation through Pay Pal, but somehow the system could not identify my information (Sorry), maybe next time. I have 2 questions:

1. Have a 2000 E320 Mercedes Benz 4 door Sedan, 3.2 engine, 90,000 miles. I installed a new battery yesterday and my radio does not want to play anymore. It shows an error. Am I supposed to reset something?
2. I did most of the required schedule B maintenance myself, but the computer is still saying that I am 1900 miles over my Schedule B maintenance. How do I tell the computer that the maintenance was done?

Thanks