Hey there @Umer gill,
Welcome to the Wefugees community and thank you for reaching out to us!
I'm sorry to hear you were told you're not allowed to take part in the class. In my research, I couldn't really find anything on why you would be denied - was it a class in the camp? Did they mention what kind of permission?
If you have a look on the following websites, there are a lot of places where you can take German language courses or "integration courses":
This is from Goethe Institute: https://www.goethe.de/en/spr/flu.html
And here is more information from the BAMF: http://www.bamf.de/EN/Willkommen/DeutschLernen/deutschlernen-node.html
Another information site on where and how to learn German: https://www.make-it-in-germany.com/en/living-in-germany/german/german-knowledge/
Please note: If you wanted to take part in an "integration course", there are restrictions after all. You can read about them and if you are eligible on the BAMF website: http://www.bamf.de/EN/Willkommen/DeutschLernen/IntegrationskurseAsylbewerber/integrationskurseasylbewerber-node.html
I hope this helps for now. Feel free to reach out to us again if you have any more questions!
Kind regards and Good Luck,