SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: DELETE FROM bb1_sessions WHERE userid='0' AND ipaddress = '18.206.15.215' AND useragent = 'CCBot/2.0 (https://commoncrawl.org/faq/)'
mysql error: Table './usr_web62_1/bb1_sessions' is marked as crashed and last (automatic?) repair failed
mysql error number: 144
mysql version: 5.5.59-0+deb7u1
php version: 5.3.29
Date: 22.08.2019 @ 00:35
Script: /
Referer: