Hi @mr-hashemian
ACF uses jQuery UI to add the date field. Unfortunately, jQuery UI doesn’t support solar calendar yet. This page should give you more idea about it: http://stackoverflow.com/questions/14110885/how-to-configure-the-jquery-ui-datepicker-to-use-a-localized-calendar.
If you really need to integrate this calendar, I suggest you hire a developer to help you out with it, and I’d recommend looking for one on https://studio.envato.com/, https://www.upwork.com/, or https://codeable.io/. I’m sorry for the inconvenience.
Thanks 🙂
