It looks like one can only added one watermark.
image.png (29.7 KB)
The API doesn’t provide any builtin method to add the watermark with repeated text. However, you can do it with multiple calls of AddWatermark method for different coordinates of the page. Please share with us the document format (PDF, image, etc.) you are working with as well as the platform (.NET or Java) for which you are using the API.