Unable to get a line on any of my O2 SIMs

[ASH27]

I have three monthly SIMs on two dual SIM Samsung S10+ phones and I have been unable to get any of them to work, except one on occasion. If I try to call either the other mobile phone or the landline it says either if it goes through "It has not been possible to connect your call" or "Mobile network not available".

I am totally worn out trying to fix this and have no idea what could be causing it.

I would go to my local O2 shop except it's more than three hours there and back and I have already had to go there twice in the last month to change the payment method and change numbers. I was told the SIMs were working fine.

It's impossible to get through to O2 on the telephone and it's so stressful trying.

Can anyone help with a suggestion or two as to what the problem might be or where I could get some help without going to the shop again?

Thanks so much.

[gmarkj]

Where and when did you get the phones and sim @ASH27 ?

If they were upgrades on existing plans then the "old" sims would still work unless you followed the "swap my sim" process.

If they are new contract sims, then they may need activating (been a while since I got a new one!).

You can call o2 using Skype on the number in the below guide:

Guide: How to find help & contact O2 

Guide: A Guide to Skype 

You mentioned that you were told the sims were working at the shop - did you verify that? Could you make calls when you were there?

It might also be worth checking these in case the area you are in has an issues:

Guide: Is the network down for me or everyone? 

Guide: How can I sort out my network issues? 

Finally, you should be able to use WiFi calling if there is an issue in your area:

https://www.o2.co.uk/connectivity/wifi-and-4g-calling 

[ASH27]

Thank you for your reply.

I guess as I still can't make calls on two out of the three SIMs I will have to make another trip to the shop!