During the questioning of two West-German students the books on the table change places while they stand up and leave the room.
The Rockpalast was held between the 15th and 16th of October 1983, yet during the party scene the television shows the event of Rockpalast 1983 while the story is placed before July 1983 (that date is displayed in the second episode, the party happened before).
In the beginning, after calling Schweppenstette, Lenora takes a can of coffee out of a drawer, which has a Russian Federation passport.
At the BBQ, when the general's son offers Stamm a beer, the bottle is open and almost horizontal, yet no beer spills out.
During the cross country run, Stamm/Rauch is wearing dark blue running shoes with light blue sole. These were part of German army outfit indeed, but introduced not until 1986. Back in 1983, the standard running shoe for German military was black with brown sole.
A 1980s pop song is playing in a West German supermarket. Grocery stores in 1983 Germany did not play music. This is a much later development.
In the Bundeswehr barracks, you see trucks in a 3-color camouflage scheme. This scheme was first introduced in 1984 - before that, they were simply painted olive drab.
The phone in the East German Stasi HQ has touch tone dialing. In the 1980s, phones in Germany (East and West) used impulse dialing instead which did not create discernible tones.
When Rauch wakes up in Bonn, he looks from the window and sees the Minster. Right beside it there is a building with an advertisement (mirror inverted) for Spanish clothing company Mango. This company was only established in 1984 and did not expand to Germany until years later.