If the mouse controls do not appear to be working correctly in the PC version of Starfield, then you can check out this troubleshooting guide from Seeking Tech.
1. For the first step, you should make sure that the game window is active if you are playing in windowed mode. You can do so by pressing the left mouse click button inside the game window or by pressing the Alt and Tab keys at the same time to switch over to Starfield.
2. You can also try pressing ALT and Enter at the same time on the keyboard.
3. Furthermore, you can try pressing the Windows key and D simultaneously.
4. If the mouse pointer is still not working correctly, then you can try removing any other peripheral devices you have plugged into your computer. In order to do so, you recommend taking the following steps:
- Save your progress and then close Starfield.
- Unplug any other controllers and other peripherals you have connected to your PC.
- Go to Settings > Accessories on Windows to double check that only your keyboard and mouse are connected as input devices.
- Launch Starfield.
5. Make sure you have the latest patch installed for Starfield.
6. If possible, try to make sure that you have the latest drivers downloaded for your mouse.
7. If the mouse is still not working correctly, you can try deleting any mods you have installed for Starfield.