I got it today evening. it comes as a sms. here it is " Congratulations WeChat user, here is your Recharge code worth Rs50 WESOUQY1JPPIGU , applicable on PayTM mobile app for a min recharge of Rs 70. Valid till 20 Feb" . I have already used it.
after giving miss call you will get this " 100% Cashback Offer: Redeem code ENTERMOBI after adding min. Rs 50 and get Rs 50 into MobiKwik Wallet. (DC/CC only). Click http://zpdi.al/MobiKwik/XLR5akgRyR "