SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: INSERT INTO bb1_searchs (searchhash,postids,showposts,sortby,sortorder,searchtime,userid,ipaddress) VALUES ('355ce6dc5feab0b317c4d0db8af02627',',105,106,107,109,110,112,113,114,117,118,126,138,139,386,387,388,389,391,393,394,395,396,397,400,401,402','0','lastpost','desc','1597107349','0','34.200.218.187')
mysql error: Field 'searchstring' doesn't have a default value
mysql error number: 1364
mysql version: 5.7.31-0ubuntu0.16.04.1
php version: 5.2.17
Date: 11.08.2020 @ 02:55
Script: /search.php?action=polls
Referer: