Normal cause is failed bulb.
You have a failed bulb on the right side.
Because you need a new bulb.
It means your turn signal bulb burnt out.
When it flashes fast it means you have a burned out bulb omn that side. Check all you lights and you'll find the one that's burned out.
A right handed person has to send a signal from the right side of the brain to the left side before the signal is sent to the body. A left handed person gets the signal direcly on the left side of the brain, therby left handed person have slightly faster reflexes.
If the right one works,it might be a bad bulb or a bad ground.
bulb is burnt
Replace the turn signal flasher relay.
More than likely you have a burnt out bulb at the front signal light, rear signal light, or brake light on the right side.
check the bulbs one is burned out
means there is a bulb burnt out on left side. check side marker/blinkers
most likely one of the bulbs is burned out