Just after updating my new iPhone 13 Pro Max to iOS 15, I made a phone call to my veterinarian and saw this perplexing error message:
I was able to make the call by tapping the “Call” button but was confused by what this meant. The issue reared its ugly head a few more times while attempting calls to people I’ve called before.
What causes the error?
Here’s the commonly accepted explanation for the “Last Line No Longer Available” error, which occurs primarily on iPhone 11, 12, and 13 models. The phone attempts to access the iPhone eSIM (electronic Subscriber Identity Module) rather than a physical SIM card. The worst-case scenario is that the iPhone owner can’t make an outgoing call.
How to fix the “Last Line No Longer Available” problem
There are a couple of ways to resolve the problem, so let’s go through ’em one by one.
Clear the Call Log
This is the method that worked for me. In the Phone app, tap the Recents button (highlighted in red at left below), tap the Clear button (highlighted in red in center image below), then tap Clear All Recents (at right below).
This does erase your call log, so if there’s anything important in there that you wish to keep — like a phone number or date/time that a call came in — you might want to capture a screenshot of it.
Remove and reinsert the SIM card
One method that has worked for some users is to power off the iPhone, remove the SIM card, wait for a minute or so, then reinsert the card before powering up the phone again.
To remove the SIM card, use either an official Apple SIM removal tool or a thin object like a straightened paperclip. Push it into the hole of the SIM tray door to open (see image below). Remove the card, then place it back into the tray and push the tray back in.
Reboot the iPhone
Being told to “turn it off and turn it on again” is a time-honored computer repair trick that dates back to the early days of personal computing. It also works for iPhones sometimes! Simply power down your iPhone, wait 30 seconds or so, then power it back on. This may help the iPhone to properly identify the SIM card in use and resolve the issue.
While Apple hasn’t resolved this issue in any of the last three major versions of iOS, there’s always a chance they could fix it in an update.
Launch Settings, scroll down to General, then tap on Software Update. If an update is available, install it to see if Apple’s iOS team has fixed the “Last Line No Longer Available” problem once and for all.