This clears any temporary app glitches.
Android: Swipe up from the bottom of your screen (or tap the recent apps button) to see open apps, then swipe Telegram away to close it. Reopen from your app drawer.
iOS: Swipe up from the bottom of the screen to bring up the App Switcher, then swipe Telegram's preview upwards to close it. Reopen from your home screen.
If the Quick Fixes Don't Work (Next Steps):
Delete Synced Contacts and Re-sync: This forces a fresh sync from scratch.
Open Telegram.
Go to Settings > Privacy and Security > Contacts.
Toggle "Sync Contacts" OFF.
Tap "Delete Synced Contacts" and confirm the deletion.
Force close Telegram (as in Step 4).
Reopen Telegram and go back to telegram number database Settings > Privacy and Security > Contacts.
Toggle "Sync Contacts" ON again.
Give it a few minutes to re-sync your contacts.
Clear Telegram Cache: Corrupted cache data can sometimes interfere.
Open Telegram.
Go to Settings > Data and Storage > Storage Usage.
Tap "Clear Telegram Cache" (or similar option) and confirm.
Restart the Telegram app.
Update Telegram App: You might be on an outdated version with a known bug.
Go to your device's app store (Google Play Store for Android, App Store for iOS).
Search for "Telegram" and see if an "Update" button is available. Install any pending updates.