Single-choice list > Required >
There is noway to empty the field because the default value is the first/specific item on the item list
***blank value on the item list is a valid value.
This is causing me issues as well especially when reviewing the entry view card. Even though I have not made a selection in the single-choice list, the value still shows up in the entry view card creating incorrect/unwanted information in the entry.
Ashwar Sadh commented
Add a trigger script for before Saving the entry and check
if(entry().field ("choice"). equals(""))