Ad Inserter menu item disappeared from WordPress top bar

I’ve noticed that since I have uploaded the W3 Total Cache plugin, the Ad Inserter menu item that sits on the top bar in WordPress Dashboard has disappeared.

I have checked and done the following:
– ‘show toolbar when visiting site’ is still checked in Users>Profile
– ‘debugging functions in admin toolbar’ is still checked in Settings>Debugging
– I have clicked on Clear Cache in three different areas in W3 Total Cache settings area.
– Today I have deactivated W3 Total Cache plugin, and still no change.

The items that show on the top menu bar in WordPress Dashboard are:
my website name / symbol to show how many plugin updates / Comments symbol / New / a Check symbol which is for Yoast SEO / Performance (which is for W3 Total Cache when activated).

What else is there to check?

The page I need help with: [log in to see the link]