Mobile Data Roaming off, still get charged
I've been using my iPhone SE 2020 with a physical German SIM card and a local eSIM.
I've turned off the mobile data roaming for the physical card.
I still get charged by this provider for Internet-usage, because the phone seems to connect for a couple KB (around 1KB to 6KB). Not every day, but up to four times per day sometimes.
Could this be that It connects via roaming when the local sim does not have any service (like when I'm travelling to more remote areas with less coverage)?
Is there anything I can do to *actually* disable roaming completely?
iPhone SE, iOS 16