My team is using a central lever that is controlled by one motor.
The problem we are having is that although the lever move upwards correctly, whenever we try to move the lever back down the lever automatically drops down with a lot of force.
The motor isn't slowly lowing it down. It's like the motor just goes into neutral and the lever falls.

Is there anything programming wise to correct this?

You would have to calculate a threshold. Do some testing and figure out at what power level your lever does not slam down. Then when u move your joystick at or below that power level, just have the power automatically set to that.

ie. If your threshold power is 5. then have it be.

if (joystick.joy1_y1 <= 5)
{
motor[MotorA] = 5;
}

or something similar.