Last line no longer available error.

It would be better if you can please re-post with a screenshot, in order to understand the phenomenon better. Images/pictures speak louder than words. 

Please understand this is a public forum: While attaching a Screenshot, do not provide any personal credentials, such as IP address, Card detail, email id, apple id, IMEI number, Serial Number, Phone number, Order ID, if you are sharing a map ensure your location is not identifiable, etc.

This is a documented problem with the iPhone Xs (see the links below). It occurs randomly, after you make a phone call. The next call you make gives you the message (below). It's been posted for months. Apparently, the only "solution" is to delete your entire recent calls list. That's not a solution, that's a BAD work-around. And it can recur.

When is Apple going to do something about it? Can we hear from Apple on this?

How to Fix iPhone Last Line no Longer Available Error

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