This is blazing so hot right now. Seriously we don't know what is wrong with MTN's server nowadays.
Just few weeks ago, a lot of people [including me ;-)] benefitted from free 7.5gb from MTN until they decided to wipe it off.
This new 'whatever-we-can-call-it' is in just simple step as below:
Then connect to the internet and continue browsing. I advise you to enjoy while it lasts before they decide to wipe it off just like they did to the free 4.5gb few weeks ago.
NB: Some claim it is unlimited, however I discovered my internet was breaking after I used 100+mb.