Can someone please help with my calculator on passing test #9

Hi can someone please me on my calculator, I think I spent a week or more on this. I refactored many times I thought I was at a point of done, but these calculator test don’t pass no matter how many variations I try. I am in the middle of another refactor and I am not moving on, until I can figure out why USER STORY 9 won’t pass for me.

TLDR: PLEASE HELP on user story 9!

USER STORY ## 9. In any order, I should be able to add, subtract, multiply and divide a chain of numbers of any length, and when I hit “=”, the correct result should be shown in the element with the id of “display”