No text message notification for ONE (and only 1) contact

[rmcnga]

I am not able to receive a notification from just one of my phone contacts when they send me a text message. 

[why00]

I had my phone number çhanged and i cant delete messages. My mailbox is full

[realaud]

Have your carrier reset your mailbox, or delete messages you don't need to save. And please don't post a question in a thread unrelated to your query, it's rude.

[Kaycaitt]

Are you using Samsung Messages?

If so, does the person you're messaging have a bell icon next to their thread?