Jira - "Custom" Custom Fields in PowerBI

Hi everyone, 

I've just hooked up my Jira instance with PowerBI. All going well other than the fact that only certain Custom Fields are pulling through.

For example, I can access "Story Points" under the field "CustomField_10117", but I cannot access a custom field that i created in Jira myself which should be "CustomField_10300".

Does anyone have any understanding of how to pull through a "custom" custom field (a custom field that i made myself in Jira).

Thanks so much.