bad service data gone dissapearing

This weekend on friday :

i bought data from mtn for 150mb at around 20:20pm i recieved .. a call which was about 10 mins via whats app

i got a msg that my data was depleted i called mtn cal center 135 i spoke to a lady who was nice but didnt help she told me that

she see's the previous 68mb i had..but not the 150mb i explained i bought it 15 mins via extra airtime she said did u get the confirmation sms

i explained i got the sms but my a data gone she explained that its hasnt updated i need to wait 2 hrs i waited 2 hrs no data was recived

saturday morning i called @ 08:35 spoke to a girl named nosipo i called and told the same story she bluntly told me that she cant help me and she needs to speak to her supervisor she put me on hold i explained that i had not used the data yet cause i didnt get it i even explained i got a call immdidatetly after buy the data she put me on hold and told me that her supervisor says ive used the data i explained its highly impossible cause that data ive been buying if for years and it last me for about 3/4 day and i was using a sumsung z flip 4 and it never consumed that much data my currrent phone is a 2007 model and only has 1 app and that whats app

they told me i can complain i asked them to escalte they refused i said can you send it to be escalted cause im gonna have to pay for somthing

i didnt use i still have not recived no help till this day