If you see old Snapchat contacts when you go to Send To.. a Snapchat, you can’t remove them from the same screen. You can still remove these contacts from showing up permanently.
1. Open Snapchat.
2. Swipe left to reveal search.
3. In Search, type the name of the old Snapchat contact you want to remove.
4. Tap the Snapchat username picture.
5. Finally, click the three dots in the top left. Tap Remove Friend.