Losing internet connectivity on carrier when roaming

• /e/ version: 2.5-t
• Device model(s): Motorola edge 20 pro and google pixel 6 pro
• Developer mode enabled: yes
• Device rooted: no
• Trackers blocker enabled: yes

Summary

When roaming, i'm losing internet connection while I make an ordinary phone call. Devices displaying this behaviour: Motorola edge 20 pro and pixel 6 pro. E os 2.5-t.

Local Friends and family who are on the carrier onto which my device falls onto for roaming (Cosmote Greece) don't have this problem (i.e. it doesn't seem to be 3g switching off issue).

VoLTE is turned on.

The problem

Mobile internet is on. I'm roaming (usually live in the uk connected to EE). Roaming in Greece and automatically connecting to Cosmote (the biggest carrier in Greece). VoLTE is on. LTE is displayed on top of the screen. I make a phone call and LTE disappears, other apps, like telegram get in "connecting..." mode. When the call ends mobile internet is restored. Same behaviour on google pixel 6 pro with the only difference that instead of LTE, 4G is displayed. My family who are live locally and using the same carrier do not have the same problem (of course they're not roaming).

This behaviour seems to be specific to roaming. Back in the UK I don't experience this problem.

What is the expected correct behavior?

Mobile internet to continue even when i'm on a call, while roaming

Technical informations

Please let me know how to provide logs and I will do

Relevant screenshots

N/A

Solutions

None. Tried changing preferred networks but none seem to work