phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '7ab47cadd1ca020ebd9eb62df860fdb2' 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 ('7ab47cadd1ca020ebd9eb62df860fdb2', -1, 1771148161, 1771148161, 'd849d800', -4, 0, 0)

Line : 187
File : sessions.php