Serial port does not exist

I have some issues with connecting a USB device to my setup.
I’ve a brand new openhabian installation and configured both options in 35 (Serial Port setup).

lusb gives me the device

Bus 001 Device 007: ID 0403:6001 Future Technology Devices International, Ltd FT232 Serial (UART) IC

sudo ls -l /dev/ttyUSB0

crw-rw---- 1 root dialout 188, 0 Dec 22 14:37 /dev/ttyUSB0

But the binding I use (DSMR Binding) keeps complaining that the serial port does not exist. Also tried it with the Serial Binding

dmesg | grep tty also gives no errors:

usb 1-1.5: FTDI USB Serial Device converter now attached to ttyUSB0

What am I missing?

Is the user that is running OH a member of the dialout group? You can run the id command and it will tell you what groups the user belongs to.

yes it is:

openhabian@openhabian:~ $ id
uid=1000(openhabian) gid=115(openhab) groups=115(openhab),4(adm),5(tty),20(dialout),24(cdrom),27(sudo),29(audio),44(video),46(plugdev),60(games),100(users),105(input),109(netdev),112(bluetooth),997(gpio),998(i2c),999(spi),1000(openhabian)
openhabian@openhabian:~ $ id openhab
uid=110(openhab) gid=115(openhab) groups=115(openhab),5(tty),20(dialout),29(audio),112(bluetooth),997(gpio)