phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '8b6bf9f6d6bf12e415b35789b3ff4e2e' for key 'phpbb_sessions.PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('8b6bf9f6d6bf12e415b35789b3ff4e2e', -1, 1771813405, 1771813405, '2d971ed8', -9, 0, 0)

Line : 187
File : sessions.php