Emails no longer appear in “Inbox” but do appear in “All Mail”

I’m using an iPad (iOS 18.7.1) with a Wi-Fi connection and Apple’s “Mail” app for sending and receiving email. My email service provider is Gmail. Two days ago, emails being sent to me have suddenly stopped appearing in my “Inbox” mailbox, but still appear in my “All Mail” mailbox. I haven’t changed any email-related settings on my iPad. This is only occurring on my iPad; emails on my iPhone remain normal, i.e., they appear in both my Inbox and All Mail mailboxes. (I’ve also tested this on both devices by sending myself an email.) Any idea why this is happening?