If there is no foam under the pickup or the foam isn’t very stiff, you could try putting some foam under them. In the states I’d say go to the hardware store and get some weatherstripping foam. Not sure what you’d have that’s similar in Germany. Anything to help stop extraneous vibration in the pickup. That may or may not help, however. It’s a cheap DIY and worth a try but the ultimate answer might be to wax or epoxy pot the pickups or install new ones.
Thanks Matt for your support
I found another thread where It reads that the screws are actually creating the microphonic
I will try to do test with or without screw aw aw (sing it like U2 would

where I’m a bit annoyed is that the bass is brand new and I own it since less than a month ...

