Dual Sim problem

[Parasetanol]

Hi,

I use Dual Sim in S22 Ultra.

I use SIM2 just for calls, no data.

SIM1 is my main sim and I use it for everything, including mobile data.

Whenever I receice a call to SIM2, SIM1 loses mobile data connection. This happens immediately when the phone rings before I answer it and the mobile data stays disconnected until I hang up the phone.

I have tried many solutions:

Cleared SIM cache

Reset network settings

Reset phone settings

Changes SIM slotes

and so on...

[BaronDigo]

Lots of dual SIM phones dont allow connection on both sims . If one sim is using call service, the other cannot use data service.. This only works on the same sim if you want to use data and voice simultaneously.

[HootleTootle]

Yep, that's the way it works. The SIM not being used for the call goes in to standby. It's a chipset limitation, as there's only one modem, so it can't be connected to two different SIMs at the same time.

[Parasetanol]

Thanks for the replies.

If that's the case as Hootle and Baron mentioned, I wonder why the Samsung Support did not mention this. They see this as an issue and guided me to clean cache, reset settings and so on. Now I'm supposed to make an error log via *#9900# (SysDump) but that's a new whole problem for me because I get errors.

I've been contacting them two times, they try to find a solution, but their response time is a little too slow (two weeks and more).

[Robin999]

There are a few flavours of dual sim. Dual sim active, Dual sim passive, dual sim standby. Samsung need to make clear which one of its models has which.

[Ahmad_Gh]

I have the same problem on my S22, the connection is lost when using both sim's and usually my phone is out of reach, the mobile data connection is not stable, for example when i am using Whatsapp ,, after typing a message i need to wait for 20 seconds to see the notification that means the message is send.

Yesterday i installed the last update dated (January 1 2023) version S901EXXU2BVKM

the problem solved!! i am using the phone since yesterday with no problems, i am using sim 1 for calls and sim 2 for mobile data 

[S23 Ultra Dual SIM]

Thanks! Now I guess i know why my mobile data suddenly jump to SIM1 although I set it such that calls and SMS using SIM1 and moble data using SIM2.

I read your answer, plus paying a SGD220 or USD160 mobile data bill to undestand this

I have my main number SIM card (rolling monthly bill) in my S23 Ultra SIM1 slot, another physical SIM card (Simba) for travel in SIM2. When travelling, I set my call and SMS to go through SIM1 phone number because I still need SMS for various home country transactions.

For mobile data, I switched it to SIM2, as per the instruction of the vendor selling me the travel SIM card (Simba). There is a clear display on my S23 screen showing these 3 settings for calls, SMS and mobile data.

When I travelled to London in mid October 23, i waited for a while when my SIM2 found its network provider then i started to use mobile data. Subsequently, I took Eurostar to Paris and back to London again. Without me realising, my S23 Ultra had started to use my SIM1 mobile data plan. Only the 2nd day after i was back to London the 2nd time that I received a warning SMS from my original SIM1 service provider which is Starhub in Singapore, that I had just used excessive mobile data. By then I already had used up SGD220 or USD160 worth of mobile data. I quickly took out the original Singapore SIM1 card (Starhub) and slot it into a spare mobile phone that I switched off mobile data altogether. I only leave this second phone to work for calls and SMS functions. 

Could Samsung please refund me SGD220? I could show proof of my various bills and setting. I have printscreen showing my 2nd SIM card (travel SIM card) usage of mobile data too.

I really do not need such a adaptive or intelligent switching function of S23 Ultra. I would rather wait for a while before my travel SIM card is activated.

[Dual sim issues]

I'm having trouble with seeing my dual sim active on 3 handsets. 

Keep saying sim2 unavailable error 

[Dual sim issues]

Where is Samsung galaxy support organization hiding 

They created the issue with 100updates

[RKyle]

I can't switch dual sim always on but I cam manually set each sim one for calls and text and.other for data I've tried everything but just can't switch dual sim always on kerry