Idea Cellular — sim card suddenly showing no service/ no range

Hi team,
My brother staying at germany and has idea sim card. His sim card was working with full recharge till now. Suddenly it started showing no service/no range. We have tried with selecting manual network and all restart and other options as well. But not sure whether this issue is due to network problem from idea side or any other roaming issue. Could you please check as it is bit urgent as he is staying out of country