phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 144 Table './db_morepc/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) VALUES ('6ab773bc4ab5e1750e5a48f77cbc0e8c', -1, 1513373795, 1513373795, '36c4b666', 0, 0)

Line : 158
File : sessions.php