phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '965ed78778e0506ed3b5fc2c5b3055f4' 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 ('965ed78778e0506ed3b5fc2c5b3055f4', -1, 1769301896, 1769301896, 'd849d814', -4, 0, 0)

Line : 187
File : sessions.php