phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 144 Table './phpbb_1/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 ('3175dce80ea86d241adb4b4a178d0d55', -1, 1429921052, 1429921052, '36a1b59c', 1, 0)

Line : 158
File : /forum/includes/sessions.php