Hello, again, Caroline. Perhaps you have already done this, but it seems to me that you need to set your TOC level formatting in the TOC dialogue, which is opened when you select Insert Table of contents rather than just choosing one of the built-in Word ones offered. In the dialogue, go to Modify, where you'll see all the TOC levels. Starting with 1, modify the font formatting as desired, being sure to base it on No Style. Do the same with each of the following levels, choosing No style each time. I think this will solve your issue.

Best,
Ulodesk