phpBB : Critical Error

Error creating new sessions

DEBUG MODE

SQL Error : 1062 Duplicate entry '8948c39c60bde213fba5f42fe95ee853' for key 1

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('8948c39c60bde213fba5f42fe95ee853', -1, 1513635743, 1513635743, '36c4b666', -4, 0, 0)

Line : 187
File : sessions.php