You should retake the photo to get more information upper and down of the sign. But I guess you didn't want to mess around with taking pictures, so try to use MS Paint (or whatever you like). You need to add black bars on the up side and down side. It won't look ideal ofc, but at least you will be able to seize the whole sign for your FB logo. Plus, your photo is a bit blurry. Again, if you don't want to retake the picture, you could get some info here https://imglarger.com/blog/how-to-make-blurry-pictures-clear/. I hope I helped you.