Updating the contact details on a messaging app

I'm trying to develop some kind of messaging app. Each time I receive a message, I saved it along with the message sender and message body to an SQLite Database.

Here's the the flow,

1. I received a message from a certain number
2. Check if that number exist in my phone's contacts
3. Saved the message on my DB with the following fields, contact_name, message_body

Problem now is when that certain contact updates it's name outside my app, how can I track or tell my app to update that name on the DB inside my app.

Thanks!