Bad customer service and undermining customers

Good day hello Peter my name is Thokozani On 6th of October 2022 I bought eggs from evergreen Kempton Park shop when I cooked them they were rotten I went to evergreen shop to tell them about their rotten eggs. They said I must bring the eggs and the slip I went home to fetch them with the eggs and the slip after that they said the supplier of eggs will contact me. The supplier phoned me the same day and promised to give me another eggs of which they didn’t. It’s now four days no phone call and eggs I spent petrol and my time going to them and going back home to fetch the eggs and the slip. Customer service is poor and they undermine customers rights, please help what steps should I take next to hold these guys to account.