This issue has been reported before but I haven't seen a general solution either.
Samsung Galaxy phones seem to be generally very temperamental when it comes to settings and retaining them reliably.
Maybe try a replacement SIM to see if it makes a difference?
Is your phone on the latest software available?
If the phone is seeing 48 as Tesco then that's an error on Samsung's part.
Hope this helps.
Hi @Anon, just wondering if you got sorted with this and how you're getting on?
Just started happening on my wifes Samsung S5.
Got this reply from 48
We're aware of Tesco taking over APN settings. They've been doing this in most Android handsets and we're unsure why they're doing that. We've already raised a case with HQ to get in touch with Tesco to find out why they're doing that and to stop it. This is still under investigation.
That's a bit of a joke seeing as you reported this in 2016.
Constantly happens abroad, failed to fix despite emailing 48 support every day for a week.
I am having the same problem even though I have never been a Tesco customer.