Dual sim and roaming abroad - can no longer activate data network

[CaptnJake]

I have a UK O2 physical sim (iPhone 13 Pro max) with roaming in contract. However, since adding a French esim (SFR) i can no longer activate data network when in France on either SIM. O2 support confirm my account is OK for this, but roaming data no longer works. I have checked APN and reset networks without any success. As far as I can see SFR and O2 network protocols look compatible, but still I get - Unable to activate data network - from both sims. Works OK on Wifi but not on phone network in France. I have deleted my VPN and stopped nearly all apps accessing mobile network without success. Any suggestions would be much appreciated. Thanks, John.

[Cleoriff]

@CaptnJake 

I'll tag @MI5 to your post. 

He has a place in France so visits often and also has a dual sim phone.

Uses the SFR network. He should be along soon so I'll leave it at that.

[Enlli]

What happens if you take the physical SIM out temporarily. Can you then select data on SFR

[MI5 · Accepted solution]

@CaptnJake 

As above. The only way to get data on both sim cards that I have found is to remove whichever is the physical sim first, set that up, then add the esim as your primary number. Once that is setup, you can switch the primary and secondary numbers around to use whichever one you want at the time.