S21 loses 4G connectivity

[Jommy_5]

My Galaxy S21 sometimes loses the internet connection despite showing the 4G icon. Switching airplane mode on and off brings it back for a minute or so, but repeated internet speed tests show progressively lower download speeds,  till it reaches 0. I'm in an area with very strong signal, and even when the connection works it can range from 200 to 20 Mbps in a matter of minutes. I've tried to reset the network settings, and Android is updated. Also changing operator, and hence SIM card, didn't helped.

By Googling the problem there are lots of users that report extremely unstable internet connections. See for example

• 4G Performance on Exynos S21 Ultra is waaayyy slower than an S10+ or S20+ 
• Mobile data not working on s21 ultra 

Are all S21 like mine?

[Hassank]

well, i will go tomorrow to samsung service center to do whatever it needs, but bear in mind that i was a customer of samsung since S1, me and my family and friends and i guarantee you that we will not stay samsung customers when its time to change our mobile due to this ***** policy.

its not fair just to accept buying a defective device for such a big amount of money and then you say we replace the board for you. i pay money $ and i didnt pay half money half potatoes exchange for a new device that must be new and defects free

[tploumen]

I totally agree. You can always try to ask for a new device. Please let us know here if you succeed...

[Praveen Kumar]

Hi all. I've been facing this exact issue recently. But I think I might have found the cause for it. In an attempt to save battery consumption, I had switched the mobile networks from 5G/LTE/3G/2G to LTE/3G/2G. This was when the problem began. Switching back to it resolved it. Hope this helps.

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Samsung S21

Baseband Version: G991BXXU3BUKG

Android 12, One UI 4.0

[Hassank]

after the software update 2 weeks ago, all was normal for 2 days only, and the problem repeats, even the cell network is lost now when the 4G stops, i went to samsung service today, they were very rude, and they wanted a video evidencing the situation and when i show them the screen recording of the incident, they said that this is not enough!!!!!!!!!!!! i was shocked, and i started screaming all over the people there, until they took again the device and handed me a receipt that they will send the device to the workshop!!! i dont know what the heck is wrong with these people nor with the device... same sim card working very normal on my A70 old phone!!!

i am so much disappointed of the device and the samsung service center 😞

[tploumen]

I'm sorry, but this is not the permanent fix. You need your mainboard replaced.

[Hassank]

lets hope they fix it in any way suitable, i am sick of this, they dont even have anyone who speaks english to explain what to do and what they will do :s

[Praveen Kumar]

Hi. I have been facing the same issue exactly after the software update 2 days back. Do you still think it is a hardware issue? Sounds more like a software problem. Let us know how your service goes !

[deedpool]

Iv got this issue as well seems to be in 5g areas or in bigger city's where there's more connectivity. I'm on ee and so are a lot of people at my work and they got no issue I'm the only on with an s21 ultra. Tried esim normal sim same thing happens

[deedpool]

It's also killing the battery.

[UltraX]

Im Italian, same problem with one s21 Ultra bought in November..In italian Samsung Forum users of s21 Ultra talk about the same problem..

Is a Hardware or Softare Problem?