phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 144 Table './unitedheroes/phpbb_sessions' is marked as crashed and last (automatic?) repair failed

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('268cf5a9f8deae47d645e03e1e7209d1', -1, 1498269643, 1498269643, '365083bb', -1, 0, 0)

Line : 187
File : sessions.php