phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 144 Table './phpbb/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 ('a5245d0ad6b40eec82e0f8f9be900281', -1, 1481141348, 1481141348, '36a1a857', 1, 0, 0)

Line : 189
File : sessions.php