Vivofit 4 device key unresponsive

The device key on my vivofit 4 is unresponsive. The display currently shows a wifi sign with the number 7582 underneath. When I take the batteries out and put them back, the display may show another symbol that I am unfamiliar with. Replacing the batteries has not made any difference. Unfortunately the support centre is closed now for the weekend (Australia). Any advice would be appreciated.