Canvas Changed Upon Opening the Project

Hello friends,

A strange occurrence happened.
I finished adding some sound effects a few days ago to my game a few days ago. I tested it and things were going well. I saved the project using “Save” and “Save Project” as I usually do.

I then shut down Unity and my PC.
today,4 days later, I open my project to find the UI Hud I made with Canvas is wayyy massive.
The game camera only shows about 1/1000 of the canvas. the canvas overlays the sprites and all the button sizes are wrong.

The canvas was originally on “screen space - overlay”
I’ve tried “screen space - camera”
I finally tried “world space” which semi-worked but the sizes are still all screwed up and I still can’t align it properly.

I haven’t updated unity or anything. It was all working fine when I shut down too.
It happened to me another time long ago. I figured it was my mistake because I wasn’t familiar with unity at all yet. I’m a bit more familiar with Unity’s UI but still not that great.

Why did this happen? is it a simple fix by changing a drop-down menu option?
Do I have to rebuild it all?

Any help would be much appreciated.

Thanks

Fixed the problem after picking this up much later.
Heres what may have happened for those who have a similar issue.

I’m not sure why but the resolution, which I had custom made in the upper left hand of the Game tab window, had been erased.

I couldn’t remember what it was so I tried clicking them all to no avail back when this problem started.

I recently started a new project and found my custom resolution (which was very not standard).

I wrote it down and opened my old project. Put in the custom resolution and POW! it works great!

I’m not sure how it changed but I did download a free asset from the unity store but never used it. I tried to open it and maybe it damaged my internal files.

Thanks and I hope someone can get use of this text.