First, double check that Airplane/Flight mode is turned off and 3G/4G reception is switched on. Also ensure that your SMS / MMS settings are correct. Use our device guides, if you need help with these steps.

• If you’re roaming, confirm that it’s switched on and enabled on your service

Second, turn your device off, wait 30 seconds and restart. Then retest. If messages are still not working, continue to the next step.

Check to see if your messaging inbox / outboxes are full and delete any un-needed messages / threads to free up space. Then check if you can send or receive further messages.

Use our device guides, if you need help deleting / freeing up space for new messages. If you’re still not able to send / receive messages, continue to the next step.

Check your Postpaid balance or Prepaid credit to ensure your service / account(s) are up to date. If you need to report a payment or request restoral see this page. If your service / account is all up to date, continue to the next step.

Optus (and other Australian telecommunication providers) is legally required to block access to devices that are not able to make emergency calls to Triple Zero (000) using VoLTE. Check if your phone is compatible using our Device Checker tool, by entering the first 8 digits of your device's IMEI (International Mobile Equipment Identity) number. Find your device's IMEI number by dialling *#06#.

If your device is not compatible, you will need a new compatible device to stay connected. You can find more information here.

Reset your device’s network configuration / network settings. Once complete, check for the issue again. See our device guides if you need help. If the issue is ongoing, continue to the next step.

Note. You may need to re-enter your WiFi password(s) after doing this.

Some final steps;

• Check that your device’s operating system is up-to-date.
• Changed recently from an iPhone / iPad to a different type of phone / tablet? Make sure you’ve de-registered from iMessage
• Advanced users with compatible devices; check your MMSC or SMSC settings
• Perform a backup, then a full restore / reset of your device.

Retest after each attempted step and if you’re still unable to send / receive messages, continue to the next step.