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==> You can retry the flow in a few minutes.
You have already linked the maximum number of phone numbers allowed for this business account. Delete a phone number to continue or request additional numbers.
By default, meta only allow maximum 2 phone numbers to one WhatsApp business account, if you need more numbers, you need to reach out to meta support to increase the allowed number limits.
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C. Phone Set up Errors
This phone number already exists in your list of phone numbers.
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