What is Null and why is it affecting me like this?

Hi! Recently, I deleted Instagram because of the major crash epidemic. I had every intention of redownloading as the solution calls for, but when I tried to do so, it wouldn't let me. I did some looking around, and noticed an app called Null in my storage That takes up some space. Whenever I try to delete it, i can press delete but it never will. And when I try to redownload instagram, the cloud icon will change to the loading icon for less than a second before switching back to the cloud 😟 It also says I have no storage even though I deleted a ton of things and cleared out my cache and other things, but I can download every app save for instagram. I've also tried logging out of my icloud and restarting my phone and deleting null some more but it isn't working. Ice read that null is caused by downloading an app that has an incomplete download, and to retry the download. But I can't remember what ever app I tried to get! If anyone can help, it'd be much appreciated. Thanks!