My farther as just bought a gainsbough 4 wheel

No, it means the Electro Brake is not engaging 100%,

Check the motor under the seat, now you will see two thick wires come from the motor , Red & Black if you look to the side of the motor you should see two thinner wires leading to the side of the motor , those are the brake power leads, (depending on Model) , has the brake seized ? or are the wires not making a good connection, these wire should lead back to the motor controller , normally a black or blue box, that is the motor controller , check connections, depending again on brand and model.

Regards
GeWiz.