Too narrow in scope - shaking constantly - useless

The adapter is shaking while driving in my cigarette lighter, which makes charging virtually impossible: he constantly loses contact. I have repeatedly reach down and "readjust" by hand - but if you have to do this several times per minute is no longer thinking about safe driving. He's just a little too narrow in scope and has therefore match. The charging cable but have fit well in the ports, the idea with the double socket like it still.
As information for other buyers: I drive a Mercedes station wagon of the 90s. Maybe it's in the cigarette lighter for other vehicles differently.

Amazon was accommodating the Exchange, since I have the 30-day return deadline just missed by my vacation - although with little discussion but ok. Within the 30 days, I would have saved me the discussion.
Where a "non-functioning" clearly mimics a defect for me because I let myself by discussions not convince them otherwise :) And then I do not care whether more or less than 30 days are around. Conclusion: I got my money back and I will look for another double adapter.