Disgusted with Rainbow chicken

I bought a 5kgs Rainbow chicken at Chickro Parow on Saturday just before closing time so when I opened the chicken it had an awful smell so my partner threw the slip away on Sunday we went chickro to return it I went to OK and my partner said they gave him a other bag of chicken which was now right but last night when I opened the the chicken the same awful smell was there to top it of there was black spots looks like its rotting😡😡 I was so upset messaged Chickro they just apologized but nothing came from it we still have the proof of payment on the phone.. Im disgusted with Chickro that sells old chicken we could have gotten sick if we had to eat from that chicken, 😡😡