Dongle lost of wireless keyboard

In most cases a lost receiver cannot be replaced.  You'll need a new keyboard.

@ejn63​ please find a solution because temporary i can't buy new keyboard 

Unless you have a bluetooth keyboard and a system with bluetooth, there is no other solution.  The receiver is matched to the keyboard -- if it's lost, both must be replaced.

Buy a new one it the best option for your at moment or try to find you lost dongle in you laptop bag or work space were you used your keyboard.