Gene symbols being split at hyphens '-'

[ibwoo]

I came across an issue with the gene MT-ND4, the MuPeXI output gene symbol is "MT".
I suspect that it is to do with some overreaching line.split('-') or something, hopefully an easy fix!
I attach an example VCF file with a mutation replicating this issue.

I should add that when I run this file through VEP externally, the gene symbol returns as expected.

mito_hyphengenesymbol_example.vcf.zip

Thanks