what is nasya in ayurveda - #25130

I am really confused about this whole Nasya thing in Ayurveda. I mean, like, I heard my friend talking about it and she swears by it for her sinus issues. I've been having a lot of congestion and these headaches that just won't go away. Doctor said my sinuses are inflamed, and I’ve tried everything from steam inhalation to over-the-counter meds but nothing really helps. I read about Nasya in Ayurveda and how it’s supposed to clear the nasal passages and improve breathing, but what is Nasya in Ayurveda exactly? Is it just some oil they put up your nose? My aunt even recommended some herbal oils, says it's calming too. Would love some insight if it really works or if it’s just another fad. Are there specific herbs I should look for? I’m kinda skeptical since my issue feels like it’s deeper than just nasal congestion, you know? Hope you guys can enlighten me a bit more on what is Nasya in Ayurveda and how it all works. Thanks!