4th axis shows up on my machine in 2 parts. One is out of bounds.

Hello, I just started using a 4th axis. I use bobcad v31. When I post my gcode of my part in on my machine. It shows the top 50% of my part fine.The bottom 50%shows up above my part in the top of my parameters. I zero and touch off. Then the top of the part is milled fine. Then my part rotates 180 and I get a z height error and machine shuts down. The bottom section is still above my top and high in z plane.I have attached a post so you can see what I'm talking about
What could it be, I have tried machine setup, new indexes etc. As always on this journey it will be something simple. Any help would be appreciated.

I think it might be the tool length G43 - you flipped the work-plane upside down

Maybe set G54 Z0 as the center-line of the rotary

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N14 G0 G54 X-3.0471 Y.4977 A0.
N15 G43 H1 Z1.
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N1870 G54 X-.8072 Y.4005 A180.
N1871 G43 H1 Z2.2

solved
solved, my machine is to simple for true 4 axis. i have to create a g55 to machine the lower part of the model.