Hi Stepan, I am not sure what happen there. That popup field is controlled by PayPal, don’t have much influence there. Have you tried again?
It’s not concerning Paypal, it’s concerning calendar week starting day, please see original thread.
I tried it yesterday after Easy Appointments plugin update (3.7.3 -> 3.9.2) and double checked calendar starting day in backoffice. It is without a change = starting day is sunday but should be monday.
Thank you, Stepan