Bonus airtime a sham

I receive countless smses from vodacom about recharging to get a promotion. I finally decided to try it out. The sms said "you will get R75 Bonus airtime valid for one day when you recharge with R15"

I recharged and got a confirmation that i had received the bonus airtime. I made a call and the R15 got depleted meaning that i didn't make use of my "bonus" airtime.

I called the call center and they told me that the bonus is only for vodacom numbers thats why my airtime got depleted.

I dont understand why it was not made clear that the "bonus" airtime was limited to vodacom numbers like they usually do on their promotions.

My undertsanding of airtime is that i can use it for any network. Had you made it explicit that this was limited, i would have not purchased this airtime as it really wasn't worth it.

Next time, please make it explicit that the so called bonuses are limited to vodacom numbers as this is really an inconvenience coupled with false advertising.