Keep in mind it takes some time.
There is a lot of examples on this forum, where people don't get why they don't gain honor back, like this one, or this one that are recent, i linked tantram's comment each time, you can see those people clearly think that they are doing well but in fact they are not.
I suspect a lot of people that are in this case are doing the same thing, maybe even without being conscious of it, some sentences are and will be considered unsportsmanlike by the system, and if reported it'll impact your progress in honor.
I guess people must remain unreported during a certain time, or be honored by a lot of players to gain back. But once you've been punished, If you want to level up, you have to be honorable in game 100% of the time.
Even one game of dishonorable behavior can derail your progress.
If you are being validly reported, it can slow your honor progress, up to virtually no progress being made. If you misbehave in games still, but it's too rare/infrequent for you to deserve a full-on punishment, you may still not be progressing in honor.
I guess it can be long and frustrating, but just keep playing and do your best to be sportsmanlike, you'll get to honor 5 :)