when I start a DFU procedure the device is advertising empty packets

[M.Anis]

I'm testing the DFU as described in this link developer.nordicsemi.com/.../a00086.html after reseting in DFU mode, when I start the device discovery, I only get empty packets

bootloader.rar
ble_app_hrs.rar
nrfjprog_win.sh

[M.Anis]

yes exactly with the button it works fine. I can also update the firmware from the service in the hrs example. but I can't get it back to the bootloader advertising as "DfuTarg" from the service.

I wasn't able to find the nrfjprog.exe to upload the bootloader so I used a script that is supposed to replace it. I'll attach everything with the question