unicast key exchange timeout

i have attached the Scree-Shots of the problematic device. cant figure out the problem..
Screen Shot 2018-02-25 at 13.47.41.png
Screen Shot 2018-02-25 at 13.48.12.png

What version of Router OS are you running? Please update to the latest one, and do not forget to update after the upgrade the firmware. This can be found under System - Routerboard. After that, reboot the router, and see if you still have problems.