Brief Red warning in dash display

Hi I drive a Vito 2019, recently it’s flashing a red picture of the van in the driver info window, where the door open warning appears. It’s the same diagram that comes up when a door isn’t shut properly except it’s in red not the normal white and doesn’t show any doors open just a picture of the whole van. And it flashes on for literally a second at most and then gone. Only seems to happen intermittently at low speeds not while on a motorway run. Everything appears to work fine. Can’t find any reference to this warning in the manual or anywhere online.

Just posting to say this fixed it, also recently left the side door open for a while in the rain and same happened till I thoroughly dried off the sensors.