nRf dongle is disconnecting automatically when try to capture

[Hari krishna]

Current result:nRF dongle is disconnecting with wireshark and Green led also stopped blinking

1. insert nRf dongle and open wireshark

2. Select nRf dongle(Green LED is blinking)

3. Select capture(Green LED is blinking)

4. Opened Capture window and discounting the nRf connect with wireshark  

let me know what is the problem here

[Kenneth]

I am not aware of anything in specific, but you can checkout the Troubleshooting guide:
https://infocenter.nordicsemi.com/topic/ug_sniffer_ble/UG/sniffer_ble/troubleshooting.html

Also I suggest to directly connect the sniffer to a USB port on the PC instead of a USB hub.

Also you can try the latest nRF Command line tools:
https://www.nordicsemi.com/Products/Development-tools/nrf-command-line-tools/download 

Kenneth