Pins may be loose.

From the luminous efficiency and Obtik this Leuhtmittel is very good.
Insert after two lights had apparently a loose connection, until I then found out when the LED lamp is difficult vin press the contacts it may happen that can push the pins in the housing.
They can pull out again and ended up staying a little loose and have to be pressed accordingly carefully into the socket.
A little fiddly but goes and if they think long, I hope, that should not be a problem.

LG Andy