There are a few reasons why your manager may be having trouble creating a Video Pin:
If you don't have a Business account. You can create one here!
If you've violated our Community Guidelines in the past, you won't be able to upload videos to Pinterest right now. We recommend reaching out to our team if you have follow up questions around this policy.
If none of those apply to you, you may be experiencing a bug. Please let us know by filing a ticket to our support team.