I am so sorry to hear of your texting troubles! We can definitely help you resolve this! One common reason for duplicate messages is if you are using a third party app. Are you using any third party messaging apps? If that is the case, you will get a notification both in the third party app, and the regular messaging app that comes with the phone.
You could resolve this by uninstalling the third party application, or you could disable the messaging notification in the stock app.
If you have not installed a third party app, and this is not the cause, please let us know and we will continue to work with you to troubleshoot this issue! I look forward to hearing back!
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