To recover your highest Snapchat Streak, follow these simple steps:
1. Launch the Snapchat app and tap on the Chats icon.
2. Locate the friend with whom your streak is lost and there’s a Restore icon next to its name, click on it.
3. Next, a pop up appears, click on the Restore option.
4. Now, your snap streak is restored with your friend. That’s it!
For more visit here: https://allinsider.net/longest-snapchat-streak/