Here are the free working DATA and Airtime

I’ll make this short. For the N5,000 free airtime, 
you’ve to make sure that your MTN line is registered,
 then dial *559*40# and you’ll be credited with N5000 airtime.
 You should get a success message saying
 “Your compensation bonus balances: Multi N5000
 and it would be valid for just 7days.
As for the unlimited data, simply 
dial *460*6# and you’ll receive a success message. 
Enable your data connection and browse.
 Once you’ve consumed almost 100mb,
 go back to your message app, 
send BT to 131 and then redial *460*6# and flexing continues. 
Always perform same procedure once you’ve consumed almost 100mb.
This works perfectly on all devices.