Thanks for your answer, rvcjew,
actually it's not off the center, it starts spilling the "paint" when I'm approximately 3 mm above the screen with the tip of the pen. It seems perfectly fine inserted, I have no magnet nearby. I don't have the old tip anymore, but it started with the new one. I'm pretty sure that everything would be okay if I could insert the old one. Or did I order the wrong tips?
Wacom Standard Schreibfedern für Digital Pro Pen 2*(10*Pack) (ack22211)
https://www.amazon.de/dp/B07DX77DN3/..._lzTiDb8DA9QQW