well i think this might be left to perhaps @markus101 or someone else more knowledgeable to answer but i can say that NzbDrone is not down in any way i can see my is working fine
can i ask what show it was you were trying to add as i can test it on mine and see if i get the same result looks like something beginning with prison from that line you posted
but it could also be Vikings from the next lot you posted which if the case i can say that vikings does work as i have that show in mine and i have had no problems
perhaps check your internet connect like load a page like google or ping a website in cmd to me just looking at it this appears to be you not being able to connect to perhaps trakt or tvdb whichever one handles the api’s or perhaps even your indexers
i am not sure how much help i can be but at least there is a few suggestions as to the possible cause and a few things for you to check out