phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '9c21eb2bff75a4c940fc5d107f3d8f68' 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 ('9c21eb2bff75a4c940fc5d107f3d8f68', -1, 1763832111, 1763832111, 'd849d815', -4, 0, 0)

Line : 187
File : sessions.php