SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: INSERT INTO bb1_sessions (sessionhash,userid,ipaddress,useragent,lastactivity,request_uri,styleid,langid,authentificationcode) VALUES ('a9b94d7728344d518a36ef95aefa9b30','0','18.222.3.255','Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.c','1715536701','board.php?boardid=575&sid=870d5d8d815727a96535bb7d52f9c0ed','0','0','')
mysql error: Duplicate entry 'a9b94d7728344d518a36ef95aefa9b30' for key 'PRIMARY'
mysql error number: 1062
mysql version: 5.6.13
php version: 7.4.33
Date: 12.05.2024 @ 19:58
Script: /board.php?boardid=575&sid=870d5d8d815727a96535bb7d52f9c0ed
Referer: http://wehrbauten.de/board.php?boardid=575&sid=870d5d8d815727a96535bb7d52f9c0ed