Why is there a grey square around the border? I just noticed it.

Because it hasn’t been properly erased around the edges, it’s still opaque.

Whoever made it either forgot to erase a layer or remove the background to it!

Cant be fixed unless someone want to erase it
Not sure if the magic wand gonna work on this thiughr maybe if you are lucky..

Contact the guy who made the sig

https://i.imgur.com/P6UV7vA.png

100FG

Don't use it unless you pay me.

The grey box is likely a low opacity layer that the original creator used as part of the design, and simply didn't notice it before submitting it
Your signature has more issues than just the grey border though
It is 400x170, which is illegal in height (maximum of 150) and is ~170 kb, which is 100 kb over the limit.
Since it's a popout, shrinking the signature would be better than cropping out 20 pixels - it's quality loss vs having a flat line, and the flat line would look worse on a popout





And never pay anyone for an illegal signature or an improper fix

The best approach would have been to approach the person who made the sig for you about the changes for an easier and likely higher quality fix

for president