Notes file disappeared

Hi everyone I am not that technical savvy so please bare that in mind if you can help? Mine is simple enough I had a specific file in notes on my devices (created on my Iphone). I just went to check some important info and everything is gone for that one folder/file. I tried reboot and everything else, I only created that specific folder a few weeks back to store all my emergency notes, so it's quite important to me. I really don't know where to start? Any help much appreciated :-)