What does this button do?

I didn’t choose any nomination for an upgrade and I saw one upgraded. I want my UPGRADE back!
What does this button do?

I didn’t choose any nomination for an upgrade and I saw one upgraded. I want my UPGRADE back!
Hey,
I see that you have Auto Upgrade enabled in your account. If you do not want your upgrades to be applied automatically, I recommend that you turn the toggle off from the settings page.