Question: iPhone X doesn't allow "Calls on Other Devices" when locked
The title basically says it all, thought it was the Folio Case but if open with phone still locked, when attempting to make a call from another device (ie iPad or iMac using FaceTime) the call "Fails".
If I unlock the phone prior to attempting the call from either device it works.
Does anyone else experience this behaviour because this was not so for iPhone SE (my previous device) - it could sit happily on the desk still in its case and calls could be made from my iMac (or iPad) without any need to go near the phone itself.
I might add incoming calls do not seem to be effected, even if the phone is locked and case closed it starts ringing and after a few seconds so do my other devices, whereby I can answer on any device to take the call. Also calls made in the car when connected via the Bluetooth system still work as expected.
I've looked through the phones settings (and searched online) but can't seem to find anything that either points to this issue or would enable "Calls on Other Devices" to work when the phone is still locked.
Any help would be appreciated.
iPhone X, iOS 11.2, 256Gb