Cannot connect to any network in the US, despite O2 travel inclusive zone

[sunmat]

I have a Pixel 3a, with a 150GB tariff which includes O2 Travel Inclusive Zone. I was able to use 4G in the US back in February with this phone and tariff. I'm back in the US today and I don't have any network whatsoever (I'm at the same place as last time).

I triple-checked that roaming is enabled on my phone, I tried selecting the carrier manually (it doesn't find any), this is the exact same phone, tariff, and place as last time so I really don't know why this happens. I checked in my profile that I have O2 Travel Inclusive Zone, and I even enabled the O2 Travel bolt to see if it would change anything, but it doesn't.

This is quiet frustrating because I signed up to a 24-month contract with the 150GB tariff at the beginning of the year precisely to allow me to use roaming when I travel to the US (I really don't need the 150GB otherwise). Before that I was on a much cheaper tariff, and out of contract. Also not having internet meant I drove "blind" (no GPS) until I resorted to stopping at a nearby Starbucks with a wifi to be able to download offline maps of the area. Not something you want to have to do with jet-lag after a 9h flight.

[Enlli]

Do you have 4G Calling (Volte) switched on?

It is a requirement to make calls in the USA

USA - Roaming with O2 

[sunmat]

How can I enable 4G calling?

On this page: https://www.o2.co.uk/help/network-coverage-and-international/wifi-and-4g-calling#google-setup

I see the following instructions for a Google phone:

Google

First you'll need to add Wifi and 4G Calling to your account. To do this sign in to My O2, go to Device details and tap Wifi and 4G Calling.

Once your new services are added to your account, follow the instructions below to enable Wifi and 4G Calling.

1. Go to Settings > Network & Internet > Advanced > Wifi Calling > make sure Wifi Calling is toggled on. To switch off Wifi Calling set the toggle to off.
    
2. Go to Settings > Network & Internet > Mobile Network > Advanced > make sure 4G Calling is toggled on. To switch off 4GCalling set the toggle to off.

But I can't find "Device details" in MyO2. I can click on "More" then "Wifi and 4G calling" but this leads to the documentation, not to any actual option to enable it. And on my phone there is no Mobile Network option under Network & Internet in my phone's settings. Searching for 4G Calling on my phone's settings yields nothing.

[gmarkj]

There are 3 steps to getting it working that I know of @sunmat 

First customer services have to enable it on your account (in a similar way to the iPhone iData).

Then you turn it on in your account.

Finally turn it on directly on your phone.

I've got it enabled on my account, but have recently moved on to the new billing platform so can I find it? nope.

Any ideas @Enlli ?

[Enlli]

@gmarkj Nope. Neither the Web or the App I'm afraid.

Not much help to people in the OPs position 

[MI5]

It's a question that has been direct to @ColinO2 previously but so far without an answer.........?

[gmarkj]

Thanks @Enlli & @MI5 

Can we get this passed on and chased for an answer please @Chris_K @Martin-O2 @Breanna ?

[sunmat]

Is this 4G Calling requirement a recent change? I had no problem roaming in the US with this phone and tariff back in February, and in the past as well (I traveled to the US frequently until the pandemic hit, with this phone and a tariff with O2 Travel Inclusive Zone).

If O2 cannot easily provide roaming in the US, it starts to make me regret taking a new 2-year contract recently, as I literally did that just for the O2 Travel Inclusive Zone.

[MI5]

@sunmat 

It's because the US networks have turned off 3g so calls cannot be made unless 4g calling is enabled.

Theoretically, 2g can be used, however, that isn't available everywhere, hence the 4g calling requirement to guarantee a calling connection.

[sunmat]

Thanks for the explanation, @MI5 .

O2 answered on Facebook and activated Wifi and 4G calling on my account. It's been nearly 24 hours now and I still don't have any network.

I can confirm that on the O2 app, in Device details, 4G Calling is shown as enabled. In my Pixel 3a's settings I can also confirm that roaming is enabled, 4G Calling is enabled (this setting appeared after they activated 4G Calling on my account so my phone definitely detected that something changed), as well as Wifi calling. I've been restarting my phone every now and then, but still nothing. It's not like I am in the middle of nowhere with no cell tower around either: the Chicago suburbs is hardly a place where I could think 4G not being available.

Any suggestion? (planning on pinging O2 again when it's been really 24 hours).