The tweak was tested and confirmed working well for on both old and new MTN SIMs. Just make sure that you use virgin SIMs (Never been used for this type of tweak) for positive response.
Before I made this post, I got MTN free 120GB on
my MTN SIM card.
Just tweak your Android phone IMEI with below:
Make sure you change the last 3 or 4 digits and you are good to go. After you've succeeded in Imei tweaking, just Text GIONEE to 131 check your data bundle dial *559# Send 2 to 131 . If you receive a negative response, try another IMEI until you receive a positive response.
Enjoy tweaking, Good luck!