Ok so my clip is doing this weird thing where it will have a black border whenever I use s_blurmocurves and motion tile (as you can see in my quick video) and I'm not sure how to get rid of it (hence why I showed you my graphs, value number, motion tile, etc.) I've tried everything, believe me. I even deleted the clip a couple of times + deleted after effects and re got it. By the way, I've used the s_blurmocurves effect before and its never done this.
P.S. someone did try to help me with this problem (shout out to Rick) but it didn't work so that's why I reuploaded this post.
There's nothing wrong. You have motion blur enabled any our motion tile effect is not pre-composed. Inevitably this will mess with how things are sampled and even the tiniest black fringe/ gap will amplify exponentially.