phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '55ca375b4408989f7ec2f828a74cf3a5' 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 ('55ca375b4408989f7ec2f828a74cf3a5', -1, 1771806998, 1771806998, '2d971ed8', -9, 0, 0)

Line : 187
File : sessions.php