Hi @Madhu23;
As Sony say:"The feature to set a ringtone for your second SIM card was available for dual SIM Xperia devices running Android 5.0 (5.1), or earlier. The feature has not been available for Xperia devices running Android 6.0 or higher. This was due to a limitation on platform level from our platform supplier. However, separate ringtones are now available in Xperia XA2, Xperia XA2 Ultra, Xperia XZ2, and Xperia XZ2 Compact.".
