Smarty Sim in Samsung suddenly not making or receiving calls

[Michael_3103338]

My wifes Samsung A40 is part of a group of three new Smary sim card users.  Today, out of the blue it stopped making or receiving calls.  Anyone know how to fix this.  Seems the A40 is compatible and VoLTE is on.

[MSF]

@Michael_3103338 May be worth checking out this article: https://help.smarty.co.uk/en/articles/8985136-checking-if-your-device-is-4g-volte-compatible.

There seem to be issues with some phones not being compatible with the Smarty protocol for VoLTE.

Have you also checked the sim in another phone?

[Michael_3103338]

It's not listed as not compatible and I don't have another phone to check - we both use the same model.  Mine seems to be working fine in the same model of phone. And anyway, why would it be working one minute and not the next?

[SmartyTrousers]

Because Three - Smarty's parent network - have recently switched off 3G in most areas. Previously, phones which were not compatible with Smarty's VoLTE (4G calling) will have been switching down to 3G to make or receive calls. Now that most of that 3G coverage has gone, phones which are not compatible with Three's/Smarty's specific VoLTE configuration are going to struggle to make or receive calls.

[MSF]

@Michael_3103338 So are you saying that her sim works in your phone or not? If it does, then perhaps her phone is kaput; if it doesn't, perhaps the sim is kaput and you need to order a specific replacement sim via dashboard on account.

[Michael_3103338]

No, not saying that, as I haven't (and won't) try swapping sim cards around.  Her phone, identical model to mine, Sim ordered about same time, intermittently stops working.  One minute it is, next it isn't, so both sim and phone work, just not consistently.  Swapping sims won't prove or disprove anything.   Mine, so far, seems OK.

[MSF]

@Michael_3103338  Surely, if the sim were to work consistently in another phone, this would show a phone fault. Likewise, if it exhibited the same problem, that would indicate a sim fault.

If you are not prepared to do the temporary swap, I'm not sure how you will be able to find out definitively - perhaps take it to a phone shop and pay to have them check?