Since installing Sequoia 15.0.1 "All Inboxes" folder no longer shows all emails from 3 different accounts

Since installing last update Sequoia 15.0.1 my ">All Inboxes" folder no longer shows all emails from 3 different accounts. I need to have the All Inboxes open to show all new emails. All information I can find online refers to opening Mail "Preferences" but there is no such thing as Preferences but only 'Settings'. And that is of no help. HELP please.

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