Sorry about late reply i resolved to investigate this and Xmas came along .. if you still need help with this it depends on whether tou are using TCPDF engine or chormium... if tcppdf it depends on which version..
for version 6 you need to edit src/ReporticoTCPDF.php you need to go to formatColumn function below and change the $k variable
$this->drawCell($wd, $this->required_line_height, "$k", "P", 0, $just, "T", $link); //PP
and for version 4 it would be in reportico_report_tcpdf.php and in format_column you will see the below and you need to change the $k variable
$this->draw_cell($wd, $this->required_line_height, "$k","P",0,$just, "T", $link); //PPP