Does anyone else have text display errors when receiving emails that contain letters with accent marks?

Does anyone else have text display errors when receiving emails that contain letters with accent marks? I notice that words like “María” show up in my email as “Mar?a” or some other incorrect character. (I hope mine shows up on the list as Maria with the letter “i” accented – if it doesn’t, then it’s just the error preventing it.)

I’m using Mail.app in MacOS Sierra 10.12.6. Is it a function of some character encoding that I need to adjust? It’s very annoying having to read Spanish with all the diacriticals replaced by random characters.

Thanks,
Rick Fernández