Chinese font punctuation incorrect widths

Hello, I'm laying out a bilingual, Traditional Chinese + English document. I'm using the client's house font, Noto Sans TC. For some reason my Indesign is using half-width characters for all the punctuation in the Chinese text, which is messing up their line-breaks and layout. The font definitely includes full-width punctuation (because they have used it on other documents), and chaning to another Chinese font displays the same punctuation correctly as full-width, but not the font I need to use. Can anyone advise on what might be causing this problem? Thank you so much!