Hello amandaw3215 ,
We are sorry for the inconvenience.
Could you please tell us what version of Acrobat you have ?
Also is it possible if you can send us the file (pdf+watermark image), so that we can test it on our end ?
To send the file, you can visit - cloud.adobe.com
1-Click on "Send & Track" tab >Click select files to Send>select choose file from my Computer or Document Cloud>Select the file>Create Link.
After the link has been created , you can then send that link in Private message .
Here is a link on How to send a Private message - How Do I Send Private Message