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 ('0a9e4030cf2f45d8886e715558bcec0e', -1, 1508711564, 1508711564, '36a7fa40', 7, 0, 0)

Line : 187
File : sessions.php