Samsung Galaxy S23 cannot make calls or send messages: a three-year-old phone has two weak points that a new one does not: a SIM tray that has been opened a few times, and an account history that includes at least one carrier change. For a Galaxy S23 that drops calls or fails to send texts, those two are worth checking early alongside signal and settings. The sequence that finds most faults is to reseat the SIM, confirm the S23's two lines are set the way you think, test with Wi-Fi Calling on, and then ask the carrier whether the line was moved, re-issued or flagged.
If you recently moved your number to the S23 from another phone, a half-finished eSIM transfer is the likeliest cause of a number that works for data but not for calls.
Differential
Likely causes of “Samsung Galaxy S23 cannot make calls or send messages”, and how to tell them apart
- 1
A SIM tray that no longer holds the card flat
What separates it Service flickers after the phone is knocked, and the carrier name comes and goes
How to confirm Switch the phone off, remove the tray, check the nano-SIM is flat and clean and reseat it firmly
- 2
An eSIM transfer that did not complete
What separates it Data works but calls and texts do not, after moving the number from an old phone
How to confirm Ask the carrier to re-provision the eSIM and scan a new QR code if they issue one
- 3
Calls and texts set to different lines
What separates it Calls work from one number and texts leave from another
How to confirm Settings, Connections, SIM manager and set both defaults to the line you want
- 4
Weak signal in a building with thick walls
What separates it Calls break up in one room
How to confirm Settings, Connections, Wi-Fi Calling to move the call onto the home network
- 5
A Messages app with chat features stuck
What separates it Texts to Android contacts sit on Sending
How to confirm Messages, Settings, Chat settings, switch chat features off and on
Before you touch a setting
Record this first — changing settings destroys the evidence
- Whether calls, texts or both fail, and in which rooms or places
- Whether the line is a physical SIM or an eSIM, and whether the number was moved recently
- The carrier and any message at the top of the screen
- The One UI version and security patch date
Try in this order
0 of 6 completedReseat the SIM
ReversibleSwitch off, use the ejector pin on the tray, check the SIM is flat and clean, and push the tray home firmly.
Check the two lines
ReversibleSettings, Connections, SIM manager: confirm which line is set for calls, texts and mobile data.
Turn on Wi-Fi Calling
ReversibleSettings, Connections, Wi-Fi Calling; indoors it can hold calls that cellular drops.
Ask about the number's history
ReversibleTell the carrier you moved or changed the number and ask them to confirm that voice and text are active on this device.
Reset the chat features
ReversibleMessages, Settings, Chat settings, off and on, then send a test text.
Reset network settings last
Reset / data riskSettings, General management, Reset, Reset network settings.
Model-specific
What is true of this model and not of its siblings
- The S23 and its SIMs
- One nano-SIM tray and one eSIM, so a phone that has been your main device for three years has probably had its SIM moved at least once.
- Emergency calls only
- The phone can reach a tower for emergencies but is not registered with your carrier; only the carrier can fix that.
Stop boundary
When this stops being a self-service repair
- !If a second SIM also fails in the S23, book a Samsung modem check
- !If the number was moved and data works but calls do not, the carrier must finish the transfer
- !If Emergency calls only persists on a working SIM, call the carrier first
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Why do calls fail after I moved my number to my S23?+
The eSIM transfer may be half finished, so data works but voice does not. The carrier can re-provision it.
Can an old SIM tray cause dropped calls?+
Yes, a nano-SIM that sits slightly loose causes service to flicker; reseat it firmly.
What does Wi-Fi Calling do on the S23?+
It carries calls and texts over Wi-Fi when cellular is weak, if your carrier supports it.
Does Reset network settings delete my messages?+
No; messages, contacts and apps stay.