if I have xi pro with dual sim and I want to use both sim call on my watch when my phone is switch of

one of my customer using watch series 5 with xi pro and she I sousing dual sim one is Airtel and one is bio and Airtel is Esim and that sim is configure in watch as cellular data and I want to know if customer on call forward on primary sim and my phone is switch off then she is not receiving any call from secondary sim but she already on call forwarding feature