When tagged in a group chat or receive a reply, the
‘@‘ counter specifying the number of tagged messages does not decrement or disappear when all the messages have been read.
Long press the
'@'symbol in the chat > clear
‘@‘ counter doesn’t disappear when the message has been read. In some cases the app normally hides it, but the badge will re-appear after some time without new replies or mentions.
‘@‘ counter disappears when the message has been read.
iPhone 8 // iOS 14.2