Error on one of wordpress multisite installation

Getting this error on a site on a multisite install

Warning: mysqli_query(): (21000/1242): Subquery returns more than 1 row in /nfs/c11/h08/mnt/206551/domains/intelligentcio.net/html/wp-includes/wp-db.php on line 1924

Cant understand why we would only be getting this error on only the one site?

Any help would be greatly appreciated

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