Use Mobile data for VoLTE calls via secondary SIM

AshesburnAshesburn Level 1
edited September 2020 in ROG Phone 2

I have purchased Asus Rog Phone II in the month of Jan '20, since then I have been using two SIM cards, JIO & VODAFONE.

I became a big fan of the feature "Use Mobile data for VoLTE calls via Secondary SIM", though I had a combination of VoLTE 4G+ Advanced LTE on Jio and just 4G on Vodafone in my circle, with the data enabled on Jio in SIM 1 slot. When I used to make calls using the non data enabled SIM which is Vodafone, automatically it used to switch the data to onto Vodafone 4G with a H or H+ symbol.

This feature worked fine until I received Android 10 update on the phone, since the update version: 17.0240.2004.9 and version before that with Android 10, this data switch feature stopped working irrespective of location where I am taking calls.

More over, I have been having serious issues on Vodafone number, I do not get the calls. It appears to be switched Off most of the time unless I switch the data to Vodafone.

I have contacted Vodafone carrier, raised a complain which went until porting to Airtel with a last minute cancellation with assurances given by Vodafone, They have replaced the SIM card 3 times, changed the plan and also got my number re-activated as a fresh customer. Nothing worked.

This issue started only after the Android 10 update, where in I started to have issues with Incoming calls on vodafone though I have the network it appears as switched off and also the feature "Use Mobile data for VoLTE calls via secondary SIM" which used to work with a combo of VoLTE 4G+ Advanced LTE on Jio and just 4G on Vodafone, data switching stopped working.

Kindly suggest on these two issues. I have performed Network reset and restored the phone as well to factory defaults.




  • Same thing happens on my 5z also, whenever someone calls to my Vodafone number and at the time of talking everything works as usual (4G)but after rejecting the call it shows H or H+ and I have to turn off the mobile data and on it again and after that it again backs to 4G but this same thing doesn't happens in Jio. Jio is working flawlessly on my device. This issue is only on Vodafone even if Airtel works perfectly.

  • It totally depends on frequency you get in your area on vodafone carrier although it shows 4g but there may be few frequency fluctuations which is main cause of your network switching after call from 4g to H or H+ may be your area has H+ frequency so strong at your area and 4g seems weaker

    Coz after call hung up phone tries to remain on strongest frequency band possible nd that is reason you get H+ as soon as you hung up

    Try to keep same H+ as soon as you hung up and see when your phone switches back to 4g automatically does it do on its own or not? Check that onces if it does than see after how many minutes does it do that?


  • Dear Debasish and Amit,

    My issue that I described is entirely different, I do not get the data when I am on active call on Secondary Sim. The auto switch data capability from Sim 1 to Sim 2 when the data is enabled on Sim 1 with the option "Use Mobile data for VoLTE calls via secondary SIM" enabled and while being on a call on Sim 2, it doesnt switch the data to Sim 2 during the call.

    Any suggestion from anyone is appreciated. I would request Asus team to help me with this situation. Thanks

  • Hi @Ashesburn,

    The network isntability plays an important role when the network is being switched. Now coming to your point. H or H+ cannot be stable enough.

    I would recommend you to visit a nearest service center where this thing can be checked in detail.

    Due to the lockdown, service centers may not be functional. Kindly call the service center before you visit one.

  • In Brazil, low level Samsung smartphones has VoLTE, super powerfull ROG II not!!!! Unbelievable!

This discussion has been closed.