USB HID keyboard sample not working on nrf52840 dongle(PCA10059)

I got an nrf52840 dongle(PCA10059) and I'm trying to run the official usb-hid-keyboard example on it, but the compilation is failing. What could be the cause, and how should I go about modifying the example code?

the toolchain and sdk is v2.9.1, board target is nrf52840dongle.

https://devzone.nordicsemi.com/cfs-file/__key/support-attachments/beef5d1b77644c448dabff31668f3a47-e7d2b73c58634eaeaa717056821bacf8/main.c

https://devzone.nordicsemi.com/cfs-file/__key/support-attachments/beef5d1b77644c448dabff31668f3a47-e7d2b73c58634eaeaa717056821bacf8/prj.conf