I am trying to fetch data from a database in Moodle with a dinamic query but I tell me that there is an error in the reading of the database:

$parts = $_POST['make']; $arr = explode(':', $parts);

$sql = "SELECT mdl_block_report_bbb_meeting.id, mdl_block_report_bbb_meeting.name, mdl_block_report_bbb_meeting.create_time, mdl_block_report_bbb_meeting.end_time, mdl_block_report_bbb_user_events.id as ueid, mdl_block_report_bbb_user_events.name as uename, mdl_block_report_bbb_user_events.join_time, mdl_block_report_bbb_user_events.left_time FROM mdl_block_report_bbb_meeting JOIN mdl_block_report_bbb_user_events ON mdl_block_report_bbb_meeting.id = mdl_block_report_bbb_user_events.meeting_id WHERE uename LIKE '%$arr%'";

$result = $DB->get_records_sql($sql);

What am I doing wrong?