I’m trying to deactivate a huge amount of users on my end around 2,000+

I tested from the All Users page, you can select/highlight at maximum of 50 users that you can see on the list (not searching) and you can do bulk action → deactivate (it works fine, deactivates all selected users)

But if you try searching or inputting a users name/email for example: search and select gary@yahoo.com, then search mika@yahoo.com, then bulk action → deactivate, it only deactivates the last selected account. 

Tried 3 or more users via this method, they are all selected via search but when using the bulk action to deactivate, it only affects the last selected account.

What am I doing wrong? Is there a proper way to deactivate huge amount of users?