You can't receive text messages if you change the card slot.

Unicom users can't send text messages for the following reasons:

1, the SMS function of mobile phone number is not enabled, so you can contact the local customer service hotline to enable it;

2. The SMS center number of this number is set incorrectly. Because the numbers of SMS centers in different provinces are inconsistent, you can contact the local customer service hotline for verification.

3. The mobile phone fee is insufficient, so you can't send and receive text messages normally, just pay the money;

4. Mobile phone number operation shields the service in the communication, and the service in the communication can be restored.