Unfortunately I can’t since I’m in Canada. I bought the phone from a UK company that makes shipping to Canada really smooth, paying VATs up front and so forth so I thought that it was all good to order and use them in Canada (Amazon in Canada sells them too, but I don’t like giving money to Amazon if I can avoid it), but I did contact Support for something and they told me that they don’t support Canada. They were very nice about it, but the bottom line is that they don’t support Canada.
I was using English (Canada) and just changed it to English (UK). Hopefully it works! 
Hi Everyone
Trying to sum up what we have learnt so far:
The restart issue combined with the request for configuration, four Users reporting that (more on Reddit to double check),
@lightrush @mellifluous @melsea @James_Meinert @wallacewells @richyboycaldo
Networks:
Canada, Public Mobile
Canada, Freedom Mobile
Canada, Telus
US, Mint mobile (2 Users)
Plus one case with two European SIMs
Do all the users mentioned have their language set to English US?
Edited to say I briefly checked Reddit and it seems most of the users affected are indeed from Canada/US.
Edited to add some more users.
I am puzzled why factory reset has not changed that. Are phones in airplane mode also restarting?
Unfortunately the issue returned once I plugged the phone into a charger. The message that quickly flashes on the screen still appears in English even though the device is set to Dutch - Netherlands.
I am also having this issue ever since I updated my phone yesterday. Mine language is English. I am in the US and on Mint mobile. I’ve had the phone for about 1 week. I bought it from Vireo .de
I have language set to English (Canada) and it was having this issue. I have since changed it to English (UK) and it still has the issue. I’m going to switch it back to English (Canada) since it seems to make no difference and I am Canadian, so… 
I’m on the Canadian Telus (Koodo is the reseller) by the way.
Resetting network settings didn’t work. I’m going for a factory reset.
Nope. Following a factory reset, the toast popped right on top of the setup wizard and the phone rebooted. There’s no SIM, no eSIM, SD card, and the device is factory reset. Not good. 
@michele.g @anon76468197 as I guess support would refuse help for Canadian user, would it be possible to add someone to the beta testers and check logs?
Damn. Sorry to hear that. I was about to do a factory reset as well. How can FP messed this up so bad? There must be a way to roll back the update. This is the equivalent of losing our phones. Mine sometimes restarts within seconds or restarting.
I’ve just tried removing the sim card to see if that would help and it makes no difference.
A rollback IS possible, but it is not for the faint of heart. https://support.fairphone.com/hc/en-us/articles/18896094650513-How-to-manually-install-Android-on-your-Fairphone
If you have already done a factory reset, this could be an option, but for the rest of us I would prefer Fairphone to resolve this regardless of where we are, since ALL data gets wiped from the phone and the website does make it clear that things can go very wrong (though in fairness, whether they could get much worse than now… I don’t know);
The fact that the factory reset didn’t resolve it means this is a far bigger issue. I contacted fair phone support via their form, since I have a European invoice and use a European SIM, while in the US - not that that should matter, because all others use networks that the fairphone 6 supported just fine up until yesterday.
You can manually install the previous version. This will cause a factory reset and you cannot relock the bootloader, as this would cause a brick.
I have the same issue, had it since late last night.
I think it is an issue with mobile connectivity. If I quickly disable cellular connectivity (airplane mode) then I can operate my phone normally (but, of course, not as a true ‘phone’…). Created an account because I need to get this sorted, but for the moment I can scrape by without.
In Canada using my phone with Bell. I’ve been able to use it just fine with its SIM card since I got it, full 5G, UWB capabilities, etc. Seamless. I bought the phone in France.
So, in the meantime, you can “use” (most) of your phone in airplane mode (wifi and bluetooth are fine). Also tried resetting network settings for normal functionality but that didn’t work, and now I see a full reset did nothing too.
Airplane mode with wifi should make it possible to have an OTA update fix this. Hope to see one within the next couple days, given that I kind of need to be able to text my mates with older devices (SMS) and make calls.
This will never happen that fast.
Now that the phone isnt rebooting constantly can you disable 5G and/or VoLTE as both could create weird issues
15.148.0 became available exactly at midnight (East Coast time) September 30th/October 1st. Is there anything significant that might have changed to cellular signal provision or something related over there at that timemark? First of a month, start of Q4.
I was able to disable 5G and so far it hasn’t rebooted yet (it has only been 3 minutes). We will see.
I first followed @fairestPhoneOthemAll ‘s recommendation and that worked fine (less of a problem at home since my provider offers VoWiFi). I was fortunately able to force 4G/3G/2G only in time before the phone restarted and I’m trying to do all of the things that were more likely to trigger the reboot (turn moments on and off, play with the settings, make and end a phone call, connect the charger) and so far the phone has not rebooted. Anyone from Europe with the new software ready to travel to the US or Canada and see if it would immediately happen to them when connecting to 5G? 
If somebody at Fairphone simply forgot the US and Canada have 5G and it should be enables, maybe it will not be FAST but at least hopefully a fairly EASY fix.
Anyway @yvmuell - gratitude for helping us get our phones seemingly back working. 
Edit: Well, it was fun while it lasted -the phone just rebooted out of nowhere while I was scrolling through something 
Hello everyone,
I have the same issue, also in Canada. I’m in Fizz so no 5G but the only thing that stops the random reboots seems to be putting airplane mode on, which is obviously not ideal because I would like to use my phone as a phone.
I also tried as someone suggested to reboot without the sim card in but that also did not work.
I’ve contacted support but I suppose it will be a while…