phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '4cf78df6e1db287c0dc1f47ea694b3a7' 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 ('4cf78df6e1db287c0dc1f47ea694b3a7', -1, 1765405938, 1765405938, 'd849d8da', -4, 0, 0)

Line : 187
File : sessions.php