International student in Germany (M 29) here. I worked under Adecco for 1 month here (for Amazon FRAX). Recently I left the job due to their behaviour and other stuffs. Today my health insurance company called and said my previous employer (Adecco) only showed to the insurance company that I worked with them for 1 day. Whereas I worked for them for 1 month. It is stated in their experience letter.
Insurance company told me to contact Adecco and fix this issue. I tried to reach them but as expected. These people are not responding.
What can I do in this situation?