i have 2 devices with same apple id one device was missing

i have iphone 6s and iphone x with same apple id just one day before missing i just turned off find my iphone in iphone x for connecting itunes and now my iphone x is in silent mode also now it is missing and device is showing in my iphone 6s in trustable devices but i cant find it please help me with a solution to get my device back and device is also online but no sim card inserted in iphone x