debit without me knowing

A purchase of R390 and R100 was made into my account at pick n pay ,i went to the store (Meadowpoint) regarding the matter and submitted all the relevant things they needed but they failed to assist me, same as headoffice still no feedback from them.They told me that they couldnt trace a purchases that went through my account ,My corncern is how come they cant trace or check footages as my money was taken out of my account by them,all i want is my money to be reversed back into my account