‘most call it "Deutschland 83" consistently. See IMDB, Wikipedia for examples.’
and here (viewtopic.php?f=7&t=53074&p=142403&hilit=deutschland+86#p142403:
‘[...] until users pointed out that even Amazon lists it under Deutschland 83 [...]’.
However, both statements are incorrect. Both IMDb, WIkipedia, as well as the opening titles, call the second series ‘Deutschland 86’.
Amazon calls the complete series ‘Deutschland’ to solve this conundrum. I think Wikipedia describes nicely what is happening here: ‘Deutschland 86 [...] a sequel to the 2015 series Deutschland 83.’
Another example of recent show that follows a simliar naming scheme is Ku’damm 56 and 59. Also here, the second series is incorrectly named on the TVDB. Yes, it obviously is the same series, just like Deutschland 83 and 86; but naming them the same the fact that the producers choose a different name for the sequel.
Please revise the naming scheme for both series. TheTVDB should reflect actual series naming, not come up with its own.