Worth checking first: confirm which camera the warning relates to (forward, side, rear, or '360 not available' which usually means several together), and note any recent work (windscreen replaced, mirror replaced, tailgate work, bumper repair). If a camera warning is still showing, the camera needs aiming.
On a Nissan that means static target calibration for each camera, run individually. The workshop sets manufacturer-spec target markers at precise distances around the car, connects via OBD with Nissan Consult 4 or a compatible diagnostic platform, and runs each camera's alignment routine in sequence. On Around View Monitor cars all four cameras are checked together.
It's a fixed £199 through our network for the camera tier: scan, all-camera alignment, certificate. If the same incident also disturbed the front radar, the radar tier is £349 and covers both in one visit. The full procedure is in our ADAS calibration guide.