Unable to set device join parameters of STEVAL STRKT01 board using Putty

Hi I have STEVAL STRKT01. I have reigestered it with TTN network. It sends the join request but it does not join the network. I came to know that there is an issue with my device join parameters so I tried to change them using putty but unable to do it. Can any 1 please guide me.

Processing command: ?devicejoinparam

Active keys:
DevEui =
JoinEui = 01 01 01 01 01 01 01 01
AppKey = 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
NwkKey = 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

I have tried using comand !appkey-xxxxxxxxxxxxxxxx