Lost the TWO Dual (SIM1 + SIM2) buttons for calls & messages after UI 3.0

[Dual-eSIM-S24Ultra]

ATTN: Samsung Support and Software Update Leadership & Development Teams.

Urgent and very important issue, we have lost the TWO Dual (SIM1 + SIM2) two buttons for making calls & sending messages after UI 3.0 update !!!!

Please read below and see attached screenshots of the issue.

All the Samsung Customers invested $1000-2000+ USD in Samsung Dual SiN mobile devices, specifically because it was always productive to manage calls and messages with TWO buttons (SIM1 and SIM2). The Samsung One UI version 3.0 update has taken away this essential feature and made our user experience inefficient, very confusing and no common sense. I updated to 3.0 in January 2021 and it has been a nightmare for the past month. Very recently there was another update and I got excited and was hopefully that Samsung Software Update Leadership & Developers would have realized their huge mistake but that was not the case, and this major issue is still not fixed!!! 

Very disappointing Samsung - please fix this issue ASAP. There are many more complaints about the same issue on several threads and everyday we have to waste time checking and waiting for a resolution. The work around to go through menu options and multiple clicks does not make any sense. Also, another solid justification for Samsung to immediately fix this issue: Our Samsung Dual SIM devices connected to cars via Bluetooth and allowed us to be hands-free, however now for both Dual SIM calls and messages scenarios, with the two buttons missing, we are no longer hands-free, and have to stop driving / pull over to click on 3-4 options to manually toggle between SIM1/SIM2, and not everyone is going to stop driving / pull over for their Dual SIM calls/messages - this is extremely DANGEROUS!!!! Samsung should consider this if they want to avoid lawsuits and more importantly the safety of lives on the road!!!!

Here is another example of the nightmare user experience: At the time of typing your text message and before clicking send if you realize you are on the wrong SIM and try to switch over, then you get an annoying alert that draft message will get discarded (See 2nd screenshot attached) .....and if you dont want to discard your draft message, then you have to cancle, copy the text message and then switch and then paste the text message before clicking send...if you do not copy/paste, then you lose your text message draft.....this is absolutely ridiculous!!!! We use to have a choice right at our finger tips to use SIM 1 or 2 for calls and messages!!!! 

Finally, I tried speaking to Samsung Support live chat (Canada, US, Singapore, and Philippines) - and none of them are able to help, they just waste time with basic troubleshooting ie. Soft Reset. I request them to escalate this issue to their Senior Ranking Support Executives and Software Update Leadership weeks ago and no response....All Samsung Dual SIM device users are impacted Globally. Please see links below: 

1) https://eu.community.samsung.com/t5/galaxy-note10-series/lost-dual-sim-choice-in-calls-and-messages-...

2) https://eu.community.samsung.com/t5/galaxy-note10-series/dual-sim-dialler-buttons-missing/td-p/26706...

3) https://eu.community.samsung.com/t5/galaxy-note20-series/dual-sim-dialler-buttons-missing/td-p/25327...

4) https://eu.community.samsung.com/t5/discussions/dialer-does-not-show-dual-sim-calling-option/td-p/21... 

5) https://us.community.samsung.com/t5/Note10/Unhidden-the-dual-sim-button/td-p/1646661

[CHMultimedia]

The files were the right ones, as your phone accepted them. Factory reset, as RedDogRabbit mentioned, does not change the firmware currently installed on your device. All it does is wipe all the user data and apps.
Were there any other information on that error screen?
And next time, I'll make sure to urge others to properly backup their data using Smart Switch PC, I am very sorry for your data loss.

[Dual-eSIM-S24Ultra]

@CHMultiMedia, I could not take screenshot of the specific error.....

no worries, about the data loss.....Quick update: i have amazing news! After checking my Google photos, atleast the "missing" screenshots were all backed up.....thank you so much for your efforts and all your help!

now before I can proceed with updating the software in the future..... I just have two options:
1) review any Samsung update notes and hopefully Samsung will include comments that Dual SIM buttons are back
2) monitor the International (EURO) Samsung Community and hope for someone to post Samsung has eventually fixed the missing buttons issue for Dual SIM users

meanwhile, final question - is it safe to not update and stay on Android 10? im assuming the only risk in not being on the latest version is missing out on security, performance and UI updates....

[CHMultimedia]

Normally yes, staying on Android 10 should not pose any security issues. There are always new flaws discovered but mass exploitation is rather infrequent. Social engineering remains the most effective attack vector.

[Dual-eSIM-S24Ultra]

OK, understood.

I'm just so happy my Dual SIM1 + SIM2 buttons are back for calls and messages 🥳😎🙏

Thanks again to All of you here for your guidance and support! Respect!

[RedDogRabbit]

You should put click on the three dot menu & choose "accept as solution" for @CHMultimedia's help & guidance. 

[Dual-eSIM-S24Ultra]

thanks for reminder...done!

[CHMultimedia]

I'm just glad to help. Have a nice day and don't hesitate to come back anytime to get help!

[RedDogRabbit]

It must be some kind of magic, going back to a previous version of android. Are you a Wizard 🧙‍♂️? 

😉

[Cassidy]

@farooqakbar

Don't forget to click on Accept as Solution on @CHMultimedia's answer...he fully deserves it !

Have a nice day 😁

[CHMultimedia]

Hi, I assumed that, as the process was successful, you no longer needed the files. Unfortunately, online space is at a premium. I'm currently reviewing my options to find the most cost-effective way to offer such firmwares conveniently for me and for everyone. I recently hit my storage limit on my personal OneDrive account so I had to clear 200GB+ of data taken by all the firmware files I had archived there. Not that it was important, I give firmware on a case-to-case basis since Samsung likes to make things complicated. It's always possible to retrieve them however.