GroupwiseRegistration notebook: ERROR: the direction cosines matrix of the fixed image is invalid!

[thewtex]

Error:

itk::ExceptionObject (0x562ce335dd80)
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Location: "unknown" 
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File: /work/build/cp38-cp38-manylinux_2_28_x86_64/_deps/elx-src/Components/Metrics/VarianceOverLastDimension/elxVarianceOverLastDimensionMetric.hxx
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Line: 71
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Description: ITK ERROR: VarianceOverLastDimensionMetric(0x562cdaf45be0): 
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ERROR: the direction cosines matrix of the fixed image is invalid!
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  The VarianceOverLastDimensionMetric expects the last dimension to represent
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  time and therefore requires a direction cosines matrix of the form:
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       [ . . 0 ]
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  dc = [ . . 0 ]
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       [ 0 0 1 ]

@N-Dekker any ideas?