Samsung galaxy s8 Dual volte not working.Hardware of Galaxy S8 is compatible with dual volte but the software is not update samsung??? How much time taken by samsung to update the s8 Dual volte problem

In S8 After Update & Upgrade Into Android Pie Hanging Problem is major issue and also Auto Brightness Problem come...Sensor is not detect proper brightness 

In my mobile galaxy s8 Volte not show in my mobile displayMy mobile Volte is On.My area Support Volte.Also samsung support airtel volte in s8.I reset my mobile but issue not solve...and also i try another sim but not show VolteThis issue is come in m...