I am sharing the method of balance chaking of all networks by entring a USSD command string like below.
To check balance: Zong
To check Zong balance type *222# and press send
To check balance:Telenor
To check Telenor balance type *444# and press send
To check balance: Ufone
To check Ufone balance type *124# and press send
To check balance: Warid
To check Glow warid balance type *100# and press send
To check balance:Mbilink
To check Jazz balance type *111# and press send