I CANT TRUST PICK N PAY'S PRICING OR BARCODES

IT IS SUCH A STRAIN TO HAVE TO REMEMBER EACH AND EVERY SHELF PRICE AT PICK N PAY , AS GOODS ARE BEING SCANNED , I HAVE TO REMEMBER WHAT THE SHELF PRICE WAS , AS SEVEN TIMES IN THE PAST I HAVE BEEN CHARGED MORE AT THE TILL THAN WHAT THE SHELF PRICE IS , CALL THE MANAGER , AND THEY SAY'' THE SYSTEM IS TO BLAME''' I SAY ******** , THE SYSTEM DOES WHAT A HUMAN PROGRAMMES IT TO DO.<br> THE LAST TIME I WAS CHARGED R17. MORE THAN THE SHELF PRICE AT THE TILL....THIS IS *****ING FROM YOUR LOYAL CUSTOMERS , AS THE PRICE OVERCHARGED IS NEVER EVER IN MY FAVOUR....WHY?<br> <br> I CANNOT EVER LET MY GUARD DOWN , AND CANNOT TRUST PICK N PAY AT ALL....WHY?