SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: DELETE FROM bb1_adminsessions WHERE userid=0 AND lastactivity<1594079220
mysql error: Can't open file: './usr_web1_2/bb1_adminsessions.frm' (errno: 24)
mysql error number: 1016
mysql version: 5.5.47-0+deb6u1-log
php version: 5.3.3-7+squeeze29
Date: 07.07.2020 @ 02:47
Script: /thread.php?threadid=188515&threadview=0&hilight=&hilightuser=0
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