A remarkably common mistake across many different levels of English speakers is the incorrect use of dice as a singular noun. Even though it may appear to be the other way around, we have the singular
and the plural
Perhaps it helps you to remember by reminding yourself of the singular-plural pairs mouse-mice and louse-lice? If you are interested in another common (even among native speakers) mistake regarding singular and plural, take a look at my previous post about phenomenon vs. phenomena.