One of my threads is now saying unknown sender what does that mean

[Android Central Question]

One of my contacts red just now saying unknown sender what is that mean

 

[mustang7757]

Which phone? This in message app?

I'll leave a Link to register so you can communicate here as a guest account you can only post questions but can't reply.
https://forums.androidcentral.com/showthread.php?t=409154

 

[B. Diddy]

Welcome to Android Central! Are you saying that the message thread now lists the contact as an unknown sender, when it was previously listed as your known contact?