Change Details

Since today I am unable to add interlanguage links to a Wikipedia article. When I try to add them, it says that I have to be logged in on both Wikipedia and the central data repository (wikidata). However, when I try to log in on Wikidata, it says that I am already logged in. Yet, I don't see my name appear in the left upper corner, as it normally always does on wikisites. When I come back to Wikipedia, it still says that I am unable to add links because I am not logged in on central data repository. I never had this before. Does anyone know the solution?