"They do not help their colleagues."
Translation:One nie pomagają swoim koleżankom.
The words "swoich kolegom" do not match each other grammatically.
OK, "koledzy" is a masculine personal plural noun, true. Now, let's look at the verb: "pomagać" (to help) takes an indirect object (the 'receiver' of the action of helping) in Dative case.
Now, you either recognize the patterns well enough already or you can check on Wiktionary (https://en.wiktionary.org/wiki/kolega#Polish), that the Dative plural form of "koledzy" is indeed "kolegom".
Now, let's see the same for "swój", remembering that it refers to a 'macsuline personal plural' noun. https://en.wiktionary.org/wiki/sw%C3%B3j#Declension_2 shows that the Dative form for both plurals is "swoim".
"swoich" is just the wrong case here, being either Genitive or Accusative.