First, I would have replied sooner, but this issue involves a client's book, and that book required a week of 14+ hour days . . . this is my first opportunity to reply.
Second, thank you to all of you who suggested checking the folio font in the master page. That was not the problem: it was correctly set to Bergamo (only the header text (not the folio) on the verso page is Trajan Pro).
However, the suggestion got me to check the actual folios on the pages themselves. A few were in Trajan. By changing them, the folios were corrected. However, of the 30 pages in the front matter with roman numeral folios, I had to change 6 of them from Trajan to Bergamo to get all the folios to be in lower case roman numerals. Changing one would fix a few pages. Then I'd have to change the next one. Remember: the master page was correct!
Walton