Note that you can only use one (3G/4G ) data connection at the same time. Check that Halebop is set as preferred SIM for data and that it has the 3G/4G connection. You may need to change the Tele2 SIM to 2G-only mode before the Halebop SIM can be set to 3G/4G.
Shouldn’t matter, as the settings are per SIM rather than per SIM slot.