Images are not printed. Why?

Hi,

I have a document originally created in MS Word 365, then exported to PDF (print quality) making about 8 MB file. The person who has printer can not print the pictures. The text prints ok but not the photos. I DO NOT HAVE a printer connected to my laptop, so I can't make changes on the printing settings. She states that previous documents I sent her before ( and it's true) she could print with pictures without problems, but this time no. Why?

Is there something I did without notice either working on MS Word or after the export to PDF? Should I make any change on my PDF settings so photos can be printed also without problems o any printer? Or does she have to work on her printer settings? I guess, something I have to change on my PDF, within the Acrobat program to solve this. What do you think? Thanks a lot for your patience.