Howto recover a nRF52840 Development Kit?

[good_night]

My program loaded to a nRF52840 DK unfortunately adresses ports P1.15 and P1.13.

Now the DK is not reachable for Segger IDE and can not be found as a USB device.

I can reach the boot mode, but how to erase or change the program on the target?

[good_night]

Any help is warm welcome for fixing this PCA10056 DK.