Second screen off center

Today I've used my HDMI cable of my second screen to play on my Playstation 4. When I'm done playing I switch the cable back to my iMac. I do this more often, but today my second screen suddenly went off center. The top navigation bar is completely missing on my second screen, but when I take a screenshot from it, it looks perfectly fine. So in my opinion it has to be something with my iMac..

Also my second screen looks a bit blurry to me..

I've did some research on the internet but no solution helped me out with this one so far. All my settings are the same as before, so that's not the issue as well. In my settings I only see 1080i, 720p and 480p as option to change my second screen, does the 1080i means something weird perhaps?

I work on a iMac 2017 (macOS Big Sur), my second screen is a DELL S2440L.

Thanks in advance for everyone's help!