Their profile photo disappears or stops updating
You can no longer see their last seen or online status
Your messages to them show only one check mark and never a second check mark
Their bio or phone number may no longer be visible
You cannot call them on Telegram
You cannot add them to a group
Their username may still exist, but their profile appears limited
If you open their chat, you may see very little account information
These signs can also happen if they changed privacy settings or deleted their account