Hi Oyomoare,
I'm sorry about the inconvenience.
Can you check if any of gene type is selected when you submit the job from "4. Gene type" section?
The error is due to empty variable of gene type but protein coding genes are selected by default so it's less likely that option gets empty.
Did you load parameter from the previous job? If that's the case there might be a bug recognising gene type.
I'll have a look and let you know.
Best,
Kyoko