Problems with the regulation with the opposing insurance

Hello together and a nice good evening, I have a question about a car damage and the resulting experience with the regulation with the opposing insurances. On May 4th I was involved in an accident without fault. I drove a long way forward road and an elderly gentleman came to meet me with his vehicle. When we were both about the same height the man just turned off instead of granting me the advance, I In the presence of the police the man immediately admitted his violation! Every accident participant got a police report in the hand where everything was recorded in writing and also the school knowledge of the master was officially held. On the evening of the accident day I went to the accident surgeon on the advice of my house doctor because I had strong stitches in the HWS and severe pain in the neck On May 5, I commissioned an expert with an expert report. In this report “almost, very close to the total damage” determined the damage. The repair sum was calculated at 7600,00 Euro incl. VAT and the residual value at 2200 Euro and fixed in the report. On May 07, I commissioned a lawyer specializing in traffic law to handle the damage and represent my interests. On May 07, I received from the Public Insurance Agency ung Braunschweig an accident questionnaire, where I had written down all the information about the vehicle and the accident. I let my lawyer know which documents including the reports of the insurance had been sent! On 15.05. I sold the vehicle at the remaining value of 2200 euros. Since 07. May I have heard nothing from the public property insurance. On 17. May as well as on 25. May I tried to contact me after the processing of my damage. At the last conversation on May 25th, I was insulted as an idiot by the clerk because I would call constantly. He could not talk to me because I am represented by the lawyer. How long should I wait now for the regulation of my damage? Why do you drag the regulation so long and why does the insurance not speak to me? How are your experiences with the regulation?