Nikon D3100 error state - says Flash required and will not focus

Had this camera around 7 years and recently it just won’t focus, with the question mark flashing and when I press to see the error it says "Subject is too dark, cannot adjust exposure, use the flash". The shutter release now when held down doesn’t result in the camera adjusting the focus so I’m stuck really not able to take photos like I was doing before. I’ve tried adjusting settings and modes and the lens. Thanks for your replies.