Mention a condition when net work done by kinetic friction is zero.

When the object is moving with constant velocity, the applied force is balanced by equal and opposite kinetic frictional force and net acceleration is zero. The positive work done by applied force is equal to the negative work done by kinetic frictional force. Therefore net work done is zero which could have been deduced from the work-energy theorem as well.

Work done = change in kinetic energy

Since the velocity of the object is constant, its kinetic energy does not change and thetotal work done on the object is zero.