Your machine is much newer than the machines I am familiar with.
Axis following error means the machine did not move as far as was expected, or moved too far.
Usually the error is caused by mechanical looseness in the drivetrain for that axis. There are couplers in the Z axis between the motor's driveshaft and the ballscrew. These can loosen up over time. Check they are tight.
The problem can also be cuased by trouble with the encoder. I don't know if the encoder is on the motor or on the machine itself. If the encoder is loose you can get these problems.
The problem can also be cuased by servo tuning. I cannot help with this. I am not familiar with the servos used on newer machines.