Files Not Downloading from Storyline - 404 Error

I've been working with a client on an eCourse that she has been deploying to multiple clients. Throughout the course there are several PDF documents that are linked in the course, and intended to open when the learner clicks on the button. Each time a new client purchases the course, I copy the generic build files, update with a name reflective of the client name, e.g., course_number_spotify and then SCORM the course, and send the SCORM off to the user to upload to their LMS. Nearly every single client has emailed us back and lets us know that the places where a user should be able to download/open the PDF files, they get a 404 error. So, each time that happens, I go back in to the .storyline files I saved under the client's name and go through each slide where there are PDFs and "reattach" the files and have to go through the SCORM process, etc. all over again. Any thoughts? Solutions?