The internet. I don't use it myself. But I am sure that if you look up either normative reasons or justifying reasons you'll find that they're the same.
Anyway, a normative reason is typically characterized as a favouring relation. So, to have a reason to believe something is to the object of a favouring relation. It is to be 'favoured' believing it. Thus normative reasons are not things, per se. They are relations between things.
There are different kinds of normative reason - instrumental, moral, epistemic (more than this, but these are the main kind). But they're all justifying reasons. Sometimes we are justified in believing something on instrumental grounds - that is, there is overall instrumental reason to believe it; sometimes moral grounds - there is overall moral reason to believe it; sometimes epistemic grounds - there is overall epistemic reason to believe it. But evidence is made of epistemic reasons (having good instrumental or moral reason for believing X does not amount to there being evidence that X is true - Buddhists, for instance, will typically only offer instrumental reasons for believing in the truth of their stupid worldview, but even if such instrumental reasons do exist, they will never constitute evidence that the view is true....which is why serious philosophers don't tend to take Buddhism seriously).
So, all normative reasons justify and 'justifications' - all of them - are made of normative reasons. "I am justified in believing X, but there is no normative reason to believe it" is a contradictory statement. But philosophers - true philosophers - are only interested in uncovering what epistemic reasons there are, for those are what evidence is made of. (To have 'evidence' that X is true is one and the same as there being epistemic reason to believe X).
Anyway, to be justified in a belief is for there to be overall normative reason for you to believe it. That's a conceptual truth.
To 'justify' a belief, however, is different. That's to do something - that's to attempt to show that there are normative reasons for the belief in question.
So, the former is a status, the latter is an activity.
For an analogy, take being hated. That's a relation. Hate is not a thing, but a relation between things. And to be hated does not require that one do anything or know that one is hated. You are hated just if someone hates you. Maybe you know that they hate you, have some idea that they hate you, or have no idea at all.
Likewise, for a belief of yours to be justified is for your possession of that belief to be something you are favoured believing. Perhaps you know that you are favoured believing it; perhaps you have some idea you are; or perhaps you have no clue. Those are all compatible with you being favoured believing it (just as having no clue you are hated is entirely compatible with you being hated).
Justifying a belief is different, as already mentioned. Justifying a belief is an activity in which one attempts to show that one has normative reason for believing what one does.
That's not to deny that sometimes an attempt to justify a belief can result in that belief coming to be one that one is in fact justified in believing. That is, sometimes we may be justified in a belief precisely because we attempted to justify it and would not have been justified in it otherwise. (Just as, by analogy, one might come to be hated because one believes everyone hates one). The point remains, however, that to be justified in a belief is not of a piece with justifying it. And thus one can be justified in a belief even if one is unable to justify it.
This we can see both from an analysis of normative reasons themselves, and independently. For we can know that not all beliefs need justifying else we would not be justified in any of our beliefs (being so requiring that we have previously accomplished the impossible task of providing an infinity of justifications).