How to make 4g Banglalink sim always free sarvice

how to make banglalink sim 4G:

1. banglalink sim 3G to 4G replace free sarvice
2. first time go to dial option

1. press the- *5000*44*1#

1. 1 minite proccessing and replay sms successfully your sim 4G ready
2. note: 2016 in buy all banglalink sim
3. 2015 - buy banglaink sim not replace
4. before 2015,  all banglalink sim 4G enable, goto banglalink sarvice point and they are helping always.
5. thank you