Hello,
Please check and run examples/DocxUtilities/replaceChartData/sample_1.php included in the package. It seems you are trying to replace a not existing chart (that the index Exception error PHP throws).
If after checking that example, you still have problems, please send the file (reporteword2017/grafica1.docx) to contact[at]phpdocx.com and we'll check it.
Regards.