Monthly data that got finished in 8days instead of a month as usual

I have been with MTN for years on the same package of data that was lasting me the full month not getting finished. On 6 February my data was loaded as usual and to my suprise the data was finished on the 14 February (only 8days compared to a full month). I contacted them to understand what was the unusual that made my data to get finished in 8 days they couldn't provide me the reason instead they sent me a summary of my data usage that meant nothing to me neither to understand the info they sent me. I only wanted them to tell me what was unusual usage. The whole month of February I didn't have data, if what happened I still don't know. And this makes it difficult for me to know what gone wrong neither what is wrong that I did for my data to last only 8days. Same happened in Jan my data got finished few days than usual and this was a suprise to me but I did address then boom in February it lasted only 8 days. MTN owes me an explanation for me to understand but they are not interested to make me understand.