Accent Menu disappears
Until yesterday, when I held down a vowel symbol (and some consonants) on my keyboard it triggered an "accent menu" bubble, which allowed me to add different accents and diacritics to the letter produced. But today, when I press a letter key, all I get is a long string of that letter repeated (such as "aaaaaaaaaaa).
This accent menu did not work in all apps, but it worked in most Apple programs such as Pages. But now it is gone from Pages too.
How can I restore the accent menu??? It is critical for typing in the accent marks in transcriptions from Arabic and Chinese--which I do a lot.
MacBook Air 13″, macOS 10.13