When you mute someone on a status update WhatsApp won’t push their updates to the Recent Updates queue. You can still view a muted status when you scroll down.
Here are the steps if you wish to unmute that particular contact.
STEP 1: Open WhatsApp.
STEP 2: Go to Status.
STEP 3: Scroll down to muted updates
section.
STEP 4: Tap and hold that contact and press Unmute.