$re = '/\[(?<OSM_Observation>[^\]]*)\]$/m';
$str = '1 2023-04-25 06-02-10112022-85346-L 7ff79dca-a39b-4b00-8b76-bee72efbcb83 CreateQPBillingEvents
Insert into tables failed-ORA-00001:Duplicate Check Fail for ORDER_ID[06-02-10112022-85346-L] TROUBLE_TICKET_ID[] CHARGETYPE [RSCN4]
2 2023-04-25 06-02-10112022-85346-L a08f16a0-2789-4216-a42d-623fae84c0b7 CreateQPBillingEvents
Insert into tables failed-ORA-00001:Duplicate Check Fail for ORDER_ID[06-02-10112022-85346-L] TROUBLE_TICKET_ID[] CHARGETYPE [RSCN3]
3 2023-04-25 06-02-10112022-85346-L 9e0f0d13-488e-4e6a-934f-a5eb36c015ca CreateQPBillingEvents
Insert into tables failed-ORA-00001:Duplicate Check Fail for ORDER_ID[06-02-10112022-85346-L] TROUBLE_TICKET_ID[] CHARGETYPE [RSCN3]
4 2023-04-25 06-02-10112022-85346-L 687e81b7-30b6-490e-90e6-552d09741a54 CreateQPBillingEvents
Insert into tables failed-ORA-00001:Duplicate Check Fail for ORDER_ID[06-02-10112022-85346-L] TROUBLE_TICKET_ID[] CHARGETYPE [RSCN4]
5 2023-04-24 06-02-10112022-85346-L 85d38933-bc8f-4c56-944b-a1acd264140c CreateQPBillingEvents
Insert into tables failed-ORA-00001:Duplicate Check Fail for ORDER_ID[06-02-10112022-85346-L] TROUBLE_TICKET_ID[] CHARGETYPE [RSCN3]';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php