We've got here as a right, both on federal as on state level:
Basic Law wrote:Article 17
[Right of petition]
Every person shall have the right individually or jointly with others to address written requests or complaints to competent authorities and to the legislature.
[...]
Article 45c
[Petitions Committee]
(1) The Bundestag shall appoint a Petitions Committee to deal with requests and complaints addressed to the Bundestag pursuant to Article 17.
(2) The powers of the Committee to consider complaints shall be regulated by a federal law.
Thus, we got a "Committee on Petitions for everything related to federal laws and federal affairs.
In my state (and in most if not all others), we've got a Committee on Petitions on the state parliament as well.
Constitution North Rhine - Westphalia wrote:Article 4
(1) The fundamental rights and civil rights laid down in the Basic Law for the Federal Republic of Germany in the version of 23 May 1949 shall form an integral part of this Constitution and directly applicable Land law.
The Petitions Committee of the state parliament helps in case of trouble with the local, regional and state authorities. Citizens can appeal to the committee with a complaint.
Anyone can submit a petition. There are no guidelines for the wording. However, the petition must be in writing, signed and stating the name and address of the petitioner. In the case of collective petitions, the address and signature of a person representing the group are sufficient. It is also possible to submit an online petition on the Landtag website.
The European Parliament has a Committee on Petitions, too, petitions can be brought forward by any EU citizen on a matter within the EU's sphere of activities.
In 2017, 11,507 petitions were received at the Committee on Petitions of the German Bundestag. That's less than the average of 17,000/year (since 1990).
In my state, it is an average of 2,100 per year.