Ok, thanks everybody for the excellent reply’s. I cleaned the glass perfectly and I leveled the bed with some precision tools shown on the picture.
After that I did a testprint and now it’s perfect. No warping, curling, just the way it used to be.
I used the 0,15mm to level the bed with the nozzle ?. That seems to be the perfect match ??
In the future this will be my way to go ??
Thanks ! and keep on printing ?