Negligence

Hi hope you doing well, yesterday on the 3rd I went to checkers festival mall during my lunch time,my colleague ask me if can buy cake for her because it was her birthday,she was buying it for the staff.when I came back she cut it among us but,it wasn't taste nice like it's been in the shelf for days,me and other three we ate but complaining about the bad taste, when last person when to eat,she realised that something is wrong that cake was green inside rotten we fell so bad how can they put something like on the shelf for their customers.i went back and asked for refund,I asked them if they check condition of their food every morning, and lady said yes, but I don't think so I'm so disappointed a big Store like checkers selling rotten food and is not for the first time,I didn't eat last night I was feeling nausea I was scared of food. I was told that first thing in the morning will call me he knock off yesterday I'm waiting for his call.can you please help me