Tagged image isn't appearing

Weber

I uploaded an image and it disappeared. I checked the artist tag and found out that it had already been uploaded, but when searching for it through the oc name (oc:firetale), it wasn’t there. It also doesn’t appears with tags such as “not spitfire”, “on lap” or “human on pony” petting, but it appeared under the “cutefire” tag.  
I have no active filters, can someone explain why did it happen, so i don’t upload an already uploaded image again?
 
image link: https://derpibooru.org/1328440
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