It's not random, all the ones your code fail have something in common, it's your job to debug your code, not ours. I already gave you some hints about it. Good luck.

Testing "sayHighHaveCompany", expecting: "say High Have Company"
Expected: "say High Have Company", instead got: "say  HighHave Company
                                                    ^     ^
                                                    |     no space here
                                                    two spaces here

Note: it's not the last word in this case that's missing the space

what does your code return for those that fail?

Not a kata issue, that's a problem with your code, look for a pattern in the input of those tests your code is failing. See where your code is adding those spaces.