S20 Update Failure - Bootloop Issue.

[Sargcj]

Hello, Im seeking some guidance on this issue I have run into with my S20 Ultra(G988U1) 118gb.

I just obtained the phone, NIB condition, clearly never opened or used previously, never dropped, etc Coming from an S8 thats solid but well aged.

Anyways, I received a request/notification to update phone via system update(OTA). It finished then rebooted the phone, and was then stuck in a bootloop with the boot splash/bios screen, aka samsung android logo screen.

I attempted clearing cache, and later factory reset via recovery menu. neither worked. None of the common fixes or resets suggested worked. Phone is currently using an ATT sim, though that will be changing soon, if it matters. 

With no progress, I flashed the matching version listed in recovery from the update, thinking maybe the download or install had an issue. (G988U1OYM3FVI5). Still looping. I then found and tried latest version Released by Samsung I could find, same issue. (G988U1OYM3FVK4)

 I then flashed the prior version, it loaded normally with no issues found so far. (G988U1UEU3FVH1) 

Based on my research & reading this is appearing to be a common issue on S20U as of recently. Is there any advice or guidance on this issue? 

The capability to update, and do so normally/officially would be preferred.

There are no issues noted so far on the rolled back version, and there are no signs of hardware issues whatsoever with the phone.

[Ekamek]

Are you able to update through OTA after flashing it?

[Sargcj]

No, it failed again when I tried.
On the last reversion to working version It popped up the update failed, to contact samsung, and hasnt prompted again.

[Ekamek]

I will download the firmware version prior to what you had, flash it then try checking for OTA updates after that. If you have done and still not working, not sure else to suggest. Good luck.

Where you getting the firmwares?

[Sargcj]

iirc it was Sammobile, it was recommended in nearly every flash related post I read as reliable.

Its too bad I couldnt find anything on Samsungs site, would rather get it from proper source.

[Ekamek]

Sammobile.com is the best I have used. Flash once, clear cache, use Smart Switch to update at least once, then go OTA route to see if you're lucky. I have not had any issues with firmware from sammobile.com since the S3 and early tablets. Wish someone here is able to help you.

[Sargcj]

I'm glad to hear its a good source to use.

I Just got prompted to update again for VI5 ota.

How do you update via SmartSwitch? I dont see a way to perform an update unless you mean a restore or move over from my old phone. its an S8 active so its far from recent/up to date.

I wont mess with it again until this weekend since I have to have a working device during the week.

But Ill probably backup latest then try some suggestions. I dont have high hopes currently though.

[00x112]

Try full fac reset from Settings menu. Then procede to flash last update according to CSC

[Sargcj]

2nd OTA attempt was after cache clear and full factory reset.

Are you suggesting to do full reset from settings app menu and then to manually flash latest firmware manually or attempt another ota?.

[00x112]

im waay late on trying to help now but do we have the issue still?