how to connect NRF52840 with android application (NRF Toolbox) via bleutooth

[nikola]

Hi ,

I am trying to connect my NRF52840 with the application NRF Toolbox using bleuutooth technology 
when I use this DK 

it works very well and the application detect the device automatically .

but when I am trying with externel debug (connecting with anrduino uno 33 ble) with this device 

It doesn't  work 

Is there  any deference between this two devices and how can I connect this device with the application ?

[Amanda Hsieh]

The allowed voltage range is 1.7–3.6 V. It should work if you give 3.6V.