Extra time airtime dissappeard

I had R2 airtime and decided take extra time for a monthly whatsapp bundle. I took the max amount of R34 leaing my airtime balance at R36 the bundle i wanted was R37 and I took again R3 after that. When i checked my balance it was all of a sudden R9 no message nothing was send as to where the R30 went. I immediatly call customer care and the lady spoke to said she couldnt anything as yet and that i must call back after 2hours but as far as she can see there was no subscriptions or out-of-bundle on my number. I also checked on the mtn app and there was nothing. But now when i called, a lady by the name of Tumi said it i had recurring data and out-of-bundle which is things i never had she could not answer how it happened but it happened and i have to cancel it. I took airtime by mtn and have to pay it back with extra but yet i did not use the R30 as it just dissappeared in less than a min