Beware of buying fish

Unbelievable from a renowned store like checkers. I bought canadian salmon from checkers on 27/01/19 to prepare for supper in 2 packs. I had to descale the small slices and as I did this I got a terrible smell from the slice of fish. 2 slices were discoloured in comparison to the other 2 slices. Further the stench fish did not leave my fingers even though I tried to use lemon to wash it. I specifically asked the person that was serving me to descale the 2nd pack before slicing, and this was not done properly. To descale sliced pieces is much more difficult than a whole fish. I am a horrified that checkers will actually sell stale fish. Let alone the inconvenience I have to take this back at my cost.