You could borrow a friend's phone ;-)

Have you checked to see whether there is a fault at your location?

https://www.o2online.de/netz/netzstoerung

Hello @HassanAbouhelal
welcome to our community. 
I am glad that you have contacted us with your service availability request. 
Have you already restarted your phone? What exactly does the display say? 
bs0 has already provided you with a link, were you able to test it? And is there a fault displayed? 
 

Kind regards 
Michael

I checked the network in the area and there is some restrictions as it says. I tried couple of times to restart my phone but still No Service. I don't have another phone at the moment to try

Hey @HassanAbouhelal,

could you give me your postal code and maybe a street name in your neighborhood? So i can look up, if there are any inconvenience :)

Greetings,
Flo

Hey @HassanAbouhelal,

Can I help you any further ?

Greetings,
Flo