I use the sim Vinaphone students, that security is 15k per month for promotional use GPRS but does not know how to check the promotional money there. you are scared to use that do not know how much they were subtracted from the main design. Anyone know how to check the design, then help me sir. Thank you! (Press * 101 # then not I have the only account where a main account and km1 km 2 km only, sir, but it did not affect the two because I have not seen for sale are deducted)