What problem is indicated by the display "gascap", when located in the area where the odometer is usually displayed?

"gascap" (the word) is displayed in the area that normally displays the
odometer.In the past, if the gas cap was not seated, or sealing, properly a
different dash light indicator/notification was used. I checked the seal and
seating of the actual gas cap. No change. Display stayed as it was. Restarted
the van. Still no change.