Samsung S5e - Book Cover Keyboard (EJ-FT720) is not working at all

Hello,
i am very pleased with /e/ on my Samsung S5e tablet.
The only thing is:
The Book Cover Keyboard (EJ-FT720) is not working at all. Completely dead.
Is that known? Do we have a solution for this problem, or is that a restriction we have to live with?
Thank you and best regards
Emanuel