your switch that tells the car that the brake is off is defective
Release the handbrake
it has a sticky handbrake switch
Either your handbrake switch is broken and will not turn off or you have low brake fluid.
Either the switch (on the handbrake) is sticking or you have a short circuit, usually caused by corroded wires or connections.
There is a button by the handbrake hold it for a few seconds it turns it off
Check the brake fluid reservoir, with some vehicles they share the low fluid light and the e-brake light.
handbrake light
The handbrake light is also the 'low fluid' warning light. It is connected to the handbrake as that ensures that it is checked every time you use the handbrake. If it remains on all the time, then check the brake fluid and top up if required. If the fluid is ok then it is probably the switch on the lever and is adjustable.
i had the same problem last month and i had find out that it was because the brake oil was running low.
Because you probably still have your handbrake on. If not, than you need to see the car-doctor.
Because the switch has either failed or come off it's mounting. There is an outside chance, if there has been work around the handbrake lever/centre console, that the switch wires might have become trapped and could be shorting out.