To stop the 'iTunes needs to check for an update to the carrier settings for your iPad' message from appearing, you can try the following steps:
1. Connect your iPad to a Wi-Fi network. The carrier settings update message is typically triggered when connected to a cellular network.
2. Open the Settings app on your iPad and tap on 'General'.
3. Scroll down and tap on 'About'.
4. Tap on 'Carrier'.
5. If there is an update available, it should appear here. Tap on 'Update' to install the update.
6. After the update is installed, the message should stop appearing.
If the message persists, you can try the following alternative steps:
1. Open iTunes on your computer.
2. Connect your iPad to your computer using a USB cable.
3. Select your iPad when it appears in iTunes.
4. Click on the 'Summary' tab.
5. Click on 'Check for Update'.
6. If an update is available, follow the on-screen instructions to install it.
If the issue continues, it's possible that there may be a problem with your iPad or your carrier's network. In this case, you may want to contact Apple Support or your carrier's customer service for further assistance.