phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '51d997c32b0e541bd374a550db9ddc6a' 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 ('51d997c32b0e541bd374a550db9ddc6a', -1, 1767194830, 1767194830, 'd849d823', -9, 0, 0)

Line : 187
File : sessions.php