phpBB : Critical Error

Error creating new sessions

DEBUG MODE

SQL Error : 1062 Duplicate entry '6b04c141445a2d4558d87e2e842e2077' for key 1

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('6b04c141445a2d4558d87e2e842e2077', -1, 1508547976, 1508547976, '36e12f5e', -9, 0, 0)

Line : 187
File : sessions.php