UI Mobile Scaling

I have a 2D UI based game and have built the foundations on the resolution of an iPhone XS in Portrait however, when I change to any other portrait resolution or aspect ratio, It doesn’t scale properly at all. I have “Scale with screen size” turned on in my canvas and I’m very confused as to what to do. I tried playing around with anchors but nothing helped so I reset them all back to the canvas centre.

If anybody could help me out I would be very happy.

How it should look like (iPhone X/XS Portrait)

How it comes out in other dimensions

set the match slider from zero to 100. So then it will keep the Height ok and trim the Width when needed.