phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '9c1959308c8acac0edd0f22e933e8179' 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 ('9c1959308c8acac0edd0f22e933e8179', -1, 1770651133, 1770651133, 'd849d88f', -4, 0, 0)

Line : 187
File : sessions.php