Monitor not displaying native resolution

In my case, the monitor itself needed to 'reboot'. Disconnect the monitor from the mains power and disconnect the display cable from the back of the pc/laptop. Wait about 30 seconds. Reconnect the mains power to the monitor. Reconnect the display cable to the pc/laptop. That fixed it for me.

I had the same problem. I was using the Acer V226WL monitor with a Geforce GTX 1050 ti graphics card. My fix was to go into the NVIDIA control panel and when I created the resolution I wanted (in my case 1680 x 1050), I also had to change the timing to get the PC to accept the resolution. I changed the timing from automatic to CVT and success! Never had another problem.