Issue with Word to PDF Conversion using Aspose.Words.jdk16

We have an issue when converting a Word document using the attached template to PDF using Aspose.Words.jdk16.

After the conversion process, certain fixed text or variable words that are replaced by the code using the placeholders embedded in the template become corrupted and revert to their original form, as shown in the screenshot below.done - escort cert continue - New.docx (153.3 KB)
Aspose Issue.jpg (177.9 KB)

@iahmed76 Could you please provide a simple code that will allow us to reproduce the problem on our side? Also, please provide the current and expected output documents in PDF format.
I have tested the scenario with the following simple code:

Document doc = new Document("C:\\Temp\\in.docx");
doc.getRange().replace(Pattern.compile("txt\\w+"), "replacement");
doc.save("C:\\Temp\\out.pdf");

And the placeholders txtxXXX are properly replaced in the output document.