There is no way, it seems, to contact their invoicing department. I believe they overcharged me. How do I contact their office?????

This page:
all contact methods
has a link to raise a support ticket and has their phone number and office hours.

-Mike (videoscribe user)

 

Hi Alison,

If you have any account or invoicing issues, please Raise a support ticket with the details and we will look into this for you.