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.