Notes file disappeared when i tried to drop and drag

Hi guys, I’m super new to using Scrivener so apologies if i’m missing something really basic. I tried to drop and drag a notes file into my manuscript to pop it into the section I wanted it to go it. And viola! It’s gone :frowning: I can’t find it anywhere. Please help! This notes file had about 1500 words in it :angry:

What is a notes file, what format, where in your Scrivener project did you try to drop it and exactly what did you do?