The Office of the Comptroller of the Currency, which had 65 examiners at JPMorgan offices, admits the lapse at a Senate Banking Committee hearing.WASHINGTON — The top U.S. bank regulator had no inkling of JPMorgan Chase & Co.'s more than $2-billion trading loss until just weeks before it became public — even though the agency had 65 examiners working full-time at the firm's Manhattan headquarters and other company offices.