I cannot make a team member inactive. the menu option is not showing. Where do I find this?

From the article

Make a user inactive

Here's how to make a user inactive on the Team page:

1. From the left menu, select Team under the Your Practice section.

2. Select the user you want to deactivate.
3. On the Status column, select Inactive from the drop-down.

4. Select Save.

Are you saying none of those menu options are available to you? It might be time to clear cache and browser history.

It never says so but try removing the team member from whichever client accounts he/she has access to first before attempting to deactivate - like I said, nowhere does it say you have to do this but since the effect is the same it is worth a try - that would be in manage team members and the individual member details.