5 Seconds of Summer - If You Don't Know Lyrics Meaning

I am a huge 5sos fangirl so I know that the boys didn't right the songs by themselves, they wrote them but with help from other people so I dont think this is something the boys related to, they did it so others could relate. But I think that this would be a song about someone was with someone they cared about but the person that they cared about didn't actually care about them, so now they're like "You can leave tomorrow, just give me one last chance."