Phone calls in standalone mode

[Bel1983]

I have the 4G Watch3. It's connected to my phone plan on O2. 

I have full functionality over bluetooth. 

Operating in standalone mode, I can text and receive texts but I can't make or receive calls or get any other notifications. I've checked the 4g signal and I have full signal, so it's not that. 

As far as I can tell, all the settings are correct. Sim is enabled, phone settings allow for texts and calls on other devices etc. When I turn everything off on my watch at home (as a control test), it says 'switch to mobile data?', I say yes and it then says, 'connect to Bluetooth'.. which I obviously can't do as I am out of range. I shouldn't need to, because I have a sim in the watch. This is the same message I get when I'm out of range of WiFi or my phone. 

Does anyone have any thoughts on what's going on at all please? The connection must be OK as I am receiving texts. Although I did see in another thread that texts connect to the phone, whereas calls bypass it. But surely if I didn't have any signal to the sims they wouldn't show as 4g? It has told me I'm registered on the network, which it wouldn't if my sim was disabled. 

Thanks

[Bel1983]

I've spent all day on with o2 and samsung customer service. Noone can suss what's wrong. O2 are sending a new sim to see if that is the issue.

[papashaun]

One other thing to check on your phone - Settings - Advanced features - Call & text on other devices - if switched off then turn this on and see if your watch is then listed. Power off phone and watch and turn them on again and see if watch then works when out of range of phone
( if that doesn't help then there are a few topics / posts on the O2 community site that may be helpful - www.community.o2.co.uk )

[papashaun]

Also seems to be some suggestion ( I don't know how true ) that with O2 that even if eg you have left your phone at home the phone still needs to be turned on, have a signal and be connected to WiFi because the watch still routes any calls through the phone over the Internet ( so you would also need mobile data turned on in the watch's settings as well as the Call & text setting on your phone I mentioned earlier ) If is the case it seems a strange way for O2 to do it as with Vodafone the watch communicates directly with the Voda network !
As I say I don't know how true this is but worth trying

[Bel1983]

TLDR at bottom.

Thanks for help guys. I spent hours in the O2 shop with them; they couldn't find anything wrong. Spent hours on the phone with Samsung; they couldn't find anything wrong. Suggestion was to return to Currys for an exchange. Decided to do that but didn't get round to it immediately. I had to restart my phone for something (already done many times); I turned it back on and it said I had data plans to choose from- only one there but I re-selected it. Didn't think any more of it, went for a walk and my phone rang.

TLDR- it seems that the sim needed to be in my phone for several days before it activated. Not sure why, but at least it is now working