Backup is the first place we can get back deleted text messages, but in case that we no have backup file, we should seek help from one tool to scan out inner data in Samsung s8, turn to Eelphone
Android Data Recovery [eelphone.com]:
1. Connect Samsung s8 to computer and launch the tool
2. Allow USB debugging and open Verify apps via USB on Samsung s8
3. Select Messages as the recovery data type
4. Recover from scan result.
Follow thhe detailed steps to
retrieve deleted texts on Samsung [eelphone.com].