Roaming permanently off, but bill shows multiple short data connections during holidays abroad

[Chaoscontrol]

This Christmas I spent 3 weeks abroad in the Philippines, where I turned off my roaming before leaving. SIM left On. After coming back, my bill showed up about 7x 100kb connections, and I was billed accordingly. Thankfully it wasn't that much (0.5€ each) THIS time.
The problem here is that last year this already happened and I was billed 70€ in Nepal, when my roaming was also off.
I have a Mi9 usually with the latest release. My partner did the same configs, but she's on a Mi6 with official global ROM, and she doesn't have a single connection. I am totally sure I never activated the roaming while abroad (I won't argue with the company, cause I cannot prove it and I already tried last year and didn't get anything).

Now, has someone detected anything like this? I am pretty annoyed, because I travel often. Next time I am surely going to completely turn off the SIM card (even when that sucks cause I might need some 2FA SMS for card payments).
Have you found any workaround? I cannot prove this is a bug (although I don't think it's something related to a specific release), but certainly it seems related to this ROM.

Any light will be appreciated. Thanks.

 

[cobben]

There is an ongoing discussion about this in a thread on the Swedroid forum.
No clear solution has appeared yet.

Datatrafik i USA trots avstängd Mobildata och Dataroaming (Telia)

Var i USA över jul och nyår. Vid avfärd från Arlanda så stängde jag av Mobildata och Dataroaming på min Huawei P30 pro, aktiverade det igen på...

swedroid.se

In short, your device does use some data traffic without your consent, probably to keep your device connected and with the correct location.

A cellphone even without any sim card at all will make and keep active a 3G HPRS+ connection to any random operator available, probably so you can make emergency calls.

Your operator "should" refund any incorrect roaming costs if you complain, some people have gotten refunds this way.

 

[Chaoscontrol]

There is an ongoing discussion about this in a thread on the Swedroid forum.
No clear solution has appeared yet.

Datatrafik i USA trots avstängd Mobildata och Dataroaming (Telia)

Var i USA över jul och nyår. Vid avfärd från Arlanda så stängde jag av Mobildata och Dataroaming på min Huawei P30 pro, aktiverade det igen på...

swedroid.se

In short, your device does use some data traffic without your consent, probably to keep your device connected and with the correct location.

A cellphone even without any sim card at all will make and keep active a 3G HPRS+ connection to any random operator available, probably so you can make emergency calls.

Your operator "should" refund any incorrect roaming costs if you complain, some people have gotten refunds this way.

I don't really think this is the case, since as I said my partner doesn't have a single connection during those same days. Plus I actually had another SIM with data connection all the time. She didn't. So if it was what you mention, her phone should have connected nonetheless to make sure where she was and what networks were available, while mine already knew thanks to the connection from the other SIM.

Also it's never happened with old phones. Next time I will try turning the entire SIM off, and if not, removing the SIM.

 

[cobben]

I don't really think this is the case, since as I said my partner doesn't have a single connection during those same days. Plus I actually had another SIM with data connection all the time. She didn't. So if it was what you mention, her phone should have connected nonetheless to make sure where she was and what networks were available, while mine already knew thanks to the connection from the other SIM.

Also it's never happened with old phones. Next time I will try turning the entire SIM off, and if not, removing the SIM.

I think the problem might be with some operators, who do not have a completely correct billing system that only bills you for your traffic, not networking traffic.

But I am just guessing.

 

[elsuzio]

Hello,

The same thing happened to me. My wife and I were abroad, the mobile data was switched off and the roaming option was also disabled.
However, she has daily connections to an unknown address ranging from 10 to 100kb while I don't (I have a Oneplus 6).

We have the same operator and I can't ask for a refund as I'm totally unable to prove that the roaming option was disabled. Plus, it's 100% a problem of the phone, I mean, it's not the first time I'm abroad, with a multitude of different phones, and it's the first time this happened to me.