I took my time to compile list of working MTN free Gigabyte imei numbers.
Take your time to tweak them.
If at first the imei numbers didn't work,  keep tweaking till you are
Successful.
( don't know how to tweak?  Read this => http://afriwap.com/android/how-to-change-imei-of-your-android-phone/ )

Below are the imei numbers to tweak
359767053317082
 
352152070072436

352152070065537

860556025322100

863619015881144

863619015890000

863619015900000

After successful tweaking send either FREE OR MIFI to 131

If you have any questions, register and reply below
Goodluck happy  tweaking

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