Hi, did you check whether you are having macros in the template. When you open word, it opens with word template. If suppose, some third party add on or macro code is there, then you bound to get those programmed results instead of regular word template.
Go to top icon left click to get word options along side with file menus like save as etc. You click word options to open a new page. There you go to Save tab in the left pane and click it. Please check the file to be saved format as default as a different . I am enclosing a default save options page in jpg format for your easy reference. If it is as same this , leave it and report and if not, correct it.
If it does not fix, then click the add on tab. You will be shown com.add on in your computer in ms office. Please see the top to see the active add ons. Leave alone inactive add ons. If you find any add on that is not trustable, just select it and disable. If there is outlook add on, which is default , leave it. If you find any third party add on just select to remove it or disable it. Then check. I think that there is a change in the save options in word causing you this. Try and report quickcly so that we can go from there