Changes to German Call Traffic
Germany will be restricting VoIP calls with a German caller ID when calling German destinations (mainly to mobile phones). These numbers must be identified and their usage permitted by the German authorities.
This legislation aims to protect the rights of consumers and to limit the inconvenience suffered by users who receive unsolicited calls or messages.
Therefore, all companies that make VoIP calls to Germany displaying a German number must fill out a document with the necessary data to identify who it belongs to. This form will be provided by your VoIP provider and sent later for registration.
Once the authentication of the number has been verified, the calls can be made without any problem. If the number is not authenticated we cannot guarantee these calls will connect.
You can find more information at the below links: