phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '7c78ab1f5fbd903ee86d55ec8f494602' 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 ('7c78ab1f5fbd903ee86d55ec8f494602', -1, 1770301765, 1770301765, 'd849d88f', -4, 0, 0)

Line : 187
File : sessions.php