One currency for website customers & visitors

Hello,
My default currency is EUR and all the product prices are in EUR.
What I need is to show all my visitors & customers prices only in UAH (Ukrainian hryvnia).

For now:
Under “Location” tab I have selected “Auto select currency”, for EUR I didn’t choose any country, and for UAH I’ve choosed all countries.

In most cases plugin works correctly and show prices in UAH, but some times visitors see prices in EUR. As I understand, this happens beacuse people are turrning off GEO location on their devices.

Is there some hook/action/function that will display prices only in one currency UAH, while on back-end administrators will be able to see prices in EUR?

Thanks!