How to remove an Org & Site Administrator when you only have Site Administrator privileges?

[Samantha Garbutt]

A former colleague was our Org & Site Administrator. I currently have Site Administrator privileges? 

How can I remove his Org Administrator status and switch it over to me?

[Brant Schroeder]

@Samantha Garbutt Welcome to the Atlassian Community

If you do not have any other org administrators you will need to contact Atlassian support and they will be able to help you with this.

https://support.atlassian.com/contact/

[Kishan Sharma]

Brant is right, only an org admin can add another user as org admin to the site, since you don't have that right currently, you should contact Atlassian Support for help.