"Unknown operation" error from an "if" statement

Hello everybody, I have written a g code file comprised of subroutines designed to provide a quick and easy way of creating supports for a coil make of copper pipe on a CNC. I tried to load the file in LinuxCNC, and I received a message that said "Near line 70 of primary cutter.ngc: unknown operation." I think the error is being triggered by the "o110 if" code on line 69, because the code "o<turn> call" appears earlier in the file without causing any problems. Can somebody tell me if I have correctly identified the problem here, and if so, how I could fix it? I have looked at the LinuxCNC documentation page for o-codes and cannot find anything wrong with that line of code. The file is attached.

Thank you,
Cameron

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