can’t remove roaming letter above signal bars

I’ve researched a lot and I can’t find any solutions to this problem. A couple of months ago I traveled by plane, and when I arrived and turned off airplane mode (I have it always turned on) I had this r above the signal bars. I think it’s because I got outside my isp area when I was on the air, but now I’m back in my city and I can’t get rid of it. I’ve trying manually selecting the isp, turning on and off the roaming and the mobile data in the configurations but nothing seems to work. What else could I try?

International roaming, forbidden networks, hidden sim toolkit on one plus 5T

I have used international roaming many times before with my one plus 5T and my native Vodafone India providers roaming plan. But this time I landed in Germany and it did not work.

I’ve been trying to debug and even on manual network selection most of the networks appear as “forbidden”. Same networks used to latch on on earlier trips. My native Vodafone provider confirms that roaming is indeed active on my plan.

I tried to reboot, reinsert the Sim but nothing works.

One of the debug steps suggested involved steps in the Sim toolkit app. This app is somehow visible under apps but I cannot seem to find it anywhere. Ideas? How can I find where it is to use it.

Even in network settings the sin toolkit option does not seem there. Other users seem to have it there. I cleared my cache but no help.

Anything else I can try to fix this?

I am on Android 8.1.0 and oxygen is version 5.1.7

Any tips are very welcome! I’m stuck here in Germany with no connectivity and my providers help desk is pretty useless.

Eg. Would inserting the Sim into another device and then back into this one help? Are there roaming related settings that need to be pushed onto the Sim?

Use Voice to make calls but not data/internet except for wifi in UK on roaming?

I am very new to this . I would like to know wether i can use my Iphone 6 with Pakistani sim to make and receive calls in UK but i would not like to it use any internet/mubile data/ data/backgroudapp data/ ANYTHING except for calls on sim. i would only like to use wifi when it available. Is it possible this way that i use roaming (my sim for making calls) but not use any DATA to save costs.