XCPEngine Regression module failure

I am having trouble figuring out why a subset of my subjects failed the regression module of XCPEngine. They ran through the 1st 3 modules, but fail in the middle of the regression module.

This is the error:
[An error occurred while processing module regress.]
· [The error was detected at signpost @2.12c.]
· [The most recent command logged was]
· [tfilter -i /data/project/vislab/a/MBAR/Resting_preproc/XCPEngine/inter/sub-MBAR20054_baseline-regress-549098651~TEMP~_DMT.nii.gz -o /data/project/vislab/a/MBAR/Resting_preproc/XCPEngine/inter/sub-MBAR20054_baseline-regress-549098651~TEMP~_DMT_TMP.nii.gz -a 2.400000 -f butterworth -h 0.01 -l 0.08 -m /data/project/vislab/a/MBAR/Resting_preproc/XCPEngine/outputs/XCP_output_MBAR_single_struc/sub-MBAR20054/baseline/prestats/sub-MBAR20054_baseline_mask.nii.gz -n /data/project/vislab/a/MBAR/Resting_preproc/XCPEngine/outputs/XCP_output_MBAR_single_struc/sub-MBAR20054/baseline/confound2/mc/sub-MBAR20054_baseline_tmask.1D -r 1 -d 2 -1]
· [For additional details, view the processing log. For improved]
· [diagnostics, increment verbosity using the -t option.]
· []
· [Processing failed to produce required output: /data/project/vislab/a/MBAR/Resting_preproc/XCPEngine/inter/sub-MBAR20054_baseline-regress-549098651~TEMP~_DMT_TMP.nii.gz]
· []
· [stream abort]

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