There are different status for phone numbers that refer to its connectivity:
Pending: This is when a business first sets up a phone number that hasn’t yet been on-boarded and approved.
Connected: The phone number is online and functioning normally.
Offline: The phone number is currently not reachable by WhatsApp servers or is not otherwise online.
Occasionally, a phone number may show one of two particular statuses that are related to quality and messaging limits: Flagged and Restricted.
Flagged: This is a warned state. When the quality rating reaches a low (red) state, the phone number is moved to a Flagged status.
If the quality rating improves to a high (green) or medium (yellow) state over 7 days, the phone number will return to a Connected status.
If the quality rating does not improve within 7 days, the number will still return to a Connected status but with a lower messaging limit imposed on it.
Restricted: Phone numbers that reach their messaging limit are moved to a Restricted state. During a Restricted state, the number will be unable to send any notification messages until the 24-hour window for sending messages is reset. They can still respond to any messages initiated by users.