Target file with untraslated segments Trados 2017

Hello everyone,

I am Francesca, currently translating a technical manual in Word format with SDL Trados 2017.

After translating the first file, I opened the preview and half the document is completely untranslated, same in saved target file. This happens where in the Word doc I have a page interruction, but there's no special tag in Trados.

Have I done something wrong during file setting? This happened already, and back then I reopened the file and got the translation from my memory, but I would like to avoid this problem in the future.

Any suggestions on how to avoid this would be really appreciated.