I think narrator and POV can be different, if the narrator is evident in the text.
Let me try. If I write:
Sienna, crawling through the underbrush as slowly and quietly as she could, felt a weird pressure building between her ears, as if some gathering storm was drawing closer…
then we’re in Sienna’s POV, close third person. If we make the narrator more evident:
Sienna crawled through the underbrush, her slow and stealthy movements a beacon drawing the attention of more and more of the under-dwellers, who misted up through the soil. Sienna felt this as a pressure building in her skull…
Hmm, that’s a fail - we’re not really in Sienna’s POV now, it’s more omniscient. Let me try again.
Sienna crawled through the underbrush with uncharacteristic caution, feeling a growing pressure inside her skull, threatening enough and somehow personal enough to puncture even her bubble of stubborn ignorance.
Maybe that’s separated the narrator’s voice - detached, a little superior - from Sienna, while still staying in her POV?
The POV I think gives us the viewpoint from which the character is experiencing the events. If in 1st person, then they’re the narrator too I think and so the two are the same. But in other POVs they are separate and could be written to be quite distinct, even contrasting.
I don’t think the narrator must be the author, either: the narrator can be some off-stage character within the story world, or some persona created for the purpose of telling the tale.