Poor service from customer care

When I couldn't access internet checked my balance to my surprise my data was gone more than 100gig to my surprised when I called the customer care was told that i migrated my contract to prepaid today something I know nothing about, asked them to check who did that request because I know nothing about it, if that was not enough I was told there's no record for it so I need to wait for 7days while the matter is being escalated wanted to know how possible and how but guess what couldn't get the answers am so disappointed as I sit here with no data, this is not right who did this can't get the answer what makes me angry is i need to wait for a week to get an explanation, if that is not enough the sms that i received with the reference number says case closed how while am on the phone looking for explanation, what kind of ********* is this, how can someone do this without a trace this is unacceptable.