Burgers with bones

I purchased burgers from chicken world in tongaat on Wednesday 29 January 2020. On Friday 31 January it was fried for lunch and on closer inspection found big pieces of bones in it. As I was working I could not go there so I phoned and spoke with the butchery manager Ishmael and he said he will get the store manager to contact me. The manager called me and he said he spoke with the person making the burger and he admitted to putting small bones in the burger. How can bones be put in the burger. He told me to come whenever I can and he will replace it. I was not happy with that then he asks me what I want. I told him previously I had the same problem with them when I bought dynamite sausages from them and it was spoilt. I took the burgers on no day 3 February 2020 and another person was at the store and he offered to replace it and I refused. To add before I could enter the store I was slipping on the tiles in the entrance. Someone had washed the floors and did not place a board to inform customers that the floor was wet. If I did not catch my balance I 2ould have had a nasty fall.