I carefully checked the inside of the tyre for objects or sharp points, found nothing. Also I cant find any hole or even a mark on the tube I replaced. Plus the tyres are Duranos, they do have puncher protection and its strange they both had the same issue, both right after a top up.

Oh and I didn't change the tube till the leak already happened so there was no puncturing of the tube during installation. And the second leak was the other wheel of which I haven't touched ever.

It's really strange because today the rear tyre that deflated overnight held its air while at work today and the tube I took out of the front has no obvious leaks when I pump it up outside of the tyre. Also the valve position was the first thing I checked when both tyres deflated, the screw was down and sealed. It's a mystery to me. I would assume someone is messing with me but I live alone and my bike is locked in my house overnight... Meh, I'll just replace everything.