Follow the below steps…
STEP 1 Recharge #100naira on your airtel sim card.
STEP 2 Send SOCIALDAY to 440 or 4403. You will get an off-point message saying“Your last call was 0.0kobo”hahahahaa imagine you sending a message and getting a call alert??? # lol
STEP 3 Keep resending and repeating
STEP 4 until your #100 naira airtime is exausted.
Now go check your MB with*123*10#you will notice you already got140MB.
This trick has been tested and confirmed working fine on all airtel sim cards either new or old