I keep getting MySQL error #1054, when trying to perform this update query:

UPDATE MASTER_USER_PROFILE, TRAN_USER_BRANCH
SET MASTER_USER_PROFILE.fellow=`y`
WHERE MASTER_USER_PROFILE.USER_ID = TRAN_USER_BRANCH.USER_ID
AND TRAN_USER_BRANCH.BRANCH_ID = 17

It's probably some syntax error, but I've tried using an inner join instead and other alterations, but I keep getting the same message:

Unknown column 'y' in 'field list' 
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