Hi. Hope somebody can advise as I've given up on Amazon support ever being able to help.

I'm trying to fill a clothing inventory template using Google sheets. For some reason the drop down menus don't have any values to choose from so I'm having to manually enter the values. In the Apparel Size Class column, I need to enter Alpha, which is apparently a valid value. However, when I do so, a little red triangle appears in the cel and I get the error "Invalid: Input must fall within specified range". I have no idea why or how to rectify this. Please help!