“Q: 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 (i.e. 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 behavior? Any help would be appreciated.”
In fact, there are a large amount of users who also have problem with this “Calls on Other Devices” feature. If you find your iPhone X/8/8 Plus or other model iPhone/iPad/iPod cannot allow calls on other devices, you may follow our tips to figure this problem out.
Sign in with same Apple ID is a must be require for users who want to use this calls on other devices feature. And you should also keep your iOS device nearby and on Wi-Fi.
If your iOS device is nearby but you still cannot receive calls on other device, you may try to turn this feature off and turn it on a few seconds later.
Users should go to: Settings >> Phone >> Calls on Other Devices
You should then toggle your nearby devices off one by one, or turn off the entire feature. And Turn them on later.
For most of the case, if you cannot easily get it fixed after kinds of restart, we suggest you to get help from professional software. Here we highly recommend you to have a try by using Tenorshare ReiBoot, this free software can assist users to refresh iPhone/iPad/iPod settings to the best condition by entering/exiting recovery mode in only one-click.
You now can take your iPhone X to check whether it allows calls on other devices when locked or not.
If all above solutions fail to fix iPhone calls on other devices not working issue. You may consider repairing your iPhone X iOS system with ReiBoot. It provides the services to fix all iOS stuck and issues without any data loss.
That’s all about how to fix iPhone/iPad/iPod doesn’t allow calls on other devices when locked. You may follow the flow to try to fix your iOS device one by one. Hope you can soon handle this problem.