SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: INSERT INTO bb2_sessions (sessionhash,userid,ipaddress,useragent,lastactivity,request_uri,styleid,langid,authentificationcode) VALUES ('f51dac3801b108dc6a6220b3ee6f1707','0','3.16.41.142','Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.c','1716264406','calendar.php?sid=c90d9361d9f53ee8e1c9c3f1ba2c5e18','0','0','')
mysql error: Duplicate entry 'f51dac3801b108dc6a6220b3ee6f1707' for key 1
mysql error number: 1062
mysql version: 4.1.22-standard
php version: 5.3.29-1+hw8
Date: 21.05.2024 @ 00:06
Script: /wbb2/calendar.php?sid=c90d9361d9f53ee8e1c9c3f1ba2c5e18
Referer: