As a person who is residing in Germany due to a national ban on deportation, you must apply for the travel document for foreigners and stateless persons ("Grey Passport" or "Grauer Pass") at your Immigration Office. You will need to prove to the authorities that it is not likely or feasible for you to obtain a passport from your home country.
If your proofs are accepted, the office will issue the the travel document.
I hope my answers were useful for you and I'll be very pleased if you contact me again with further questions. I'm a member of the MBEON-staff and I‘ll be glad to guide over a longer period of time. Mbeon is an online consultancy for migrants via the mbeon-app, which you can install on your smartphone for free. Download it via App Store or Google Play Store. You'll find me In the mbeon-app under my name „München, Frau Müller“ and get confidential one-to-one advice in a safe virtual room, where nobody can wiretap messages. More informations:www.mbeon.de.