phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 'session_user_id'

INSERT INTO satshop_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('67902399068b0909bb4a57e0504eeb5c', -1, 1728658368, 1728658368, '2cc87ad6', 12, 0, 0)

Line : 189
File : sessions.php