bad service and lies in between

went to Maponya to buy camp chairs, the quality is so bad that when you sit it starts running. I took it back they I'm told they need the whole order, told them I have already used the bedding so the manager said hey cant credit the chairs. he told me head office said I'm overweight and when I phone the head office I'm told they haven't receive a credit note that I signed at the branch on the 31/12/2018. The manager kept the goods at the branch and told me to come fetch them and I have to pay home choice