phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'ac18a9de8ffde5b7b2f89c73b371a71a' 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 ('ac18a9de8ffde5b7b2f89c73b371a71a', -1, 1765774661, 1765774661, 'd849d836', -4, 0, 0)

Line : 187
File : sessions.php