Weird id_key problem

Per my boss, Ken Vaughn:

There is a particular record in a custom table as seen through a custom tab in Tessitura that refuses to update.  The error message is as follows:

Row changed between retrieve and update.

No changes made to database.

UPDATE hos_gen_info SET pmt_recd = 'Y' WHERE id_key = 0 AND customer_no = 3004517 AND voice_type = 'Tenor' AND app_type = 'S' AND resident_status = 'US' AND other_citizen = '' AND recommendation_1 = 'Maitland Peters, Voice Department Chair, Manhattand Sch' AND recommendation_2 = 'Gordon Ostrowski, Director of Opera Studies, Manhattan' AND recommendation_3 = '' AND english = 'Native' AND german = '1' AND italian = '2' AND french = '2' AND spanish = '3' AND sings_languages = 'Latin: 4 years' AND pmt_info = 'Visa' AND pmt_recd = 'N' AND prior_applicant = 'Yes' AND prior_applicant_years = '2008' AND prior_finalist = 'No' AND prior_finalist_years = '' AND other_name_used = '' AND notes1 = 'Manhattan School of Music: Professional Studies (tba 2010), Master of Music (2009). Eastman School of Music: Bachelor of Music (2007)' AND notes2 = 'Teachers: Maitland Peters, Cynthia Hoffmann, Constance Haas, Gisela Goettling.  Coaches: Rachelle Jonck, Lucy Yates, Kenneth Merrill, Shane Schag, Thomas Muraco, William Tracy' AND notes3 = 'Teachers: Rhoda Levine, Gretchen Sonstroem. Coaches: Catherine Malfitano, Dona D. Vaughn, Carolyn Marlow.' AND notes4 = 'Richard Rodgers Scholar/Rodegers and Hammerstein Foundation Award (2010), Rodgers and Hammerstein Foundation Award (2008-2009), Howard Hanson Scholar (2003-2007).' AND notes5 = 'Bel Canto at Caramoor Young Artist (2009), OperaWorks (2008)'

It would make sense to go to the id_key and notice that there are over 400 records added to that table with an id_key = 0 (which needs addressing, of course), but whenever any information is updated for that particular record we get that error.

Any ideas?

Thanks in advance, Tessiturians.

BONUS TRIVIA:  Julio Iglesias used to play goal for Real Madrid's second team.