Unable to reset dropdown value to -1

I have a dropdown for selecting your country. When the user goes to the page, the dropdown's value is initially -1, with nothing selected. When the user selects anything, navigates away from the page, and navigates back, I set the value to -1, to try to unselect an option in the dropdown. However, this just sets it to the first country option.

This seems like a bug to me, lemme know if there's a good way around this. Thanks.