PHIDAV7, we know the importance of being able to monitor the users on your account. We are here to help review your options.
Since we want all our customers to have piece of mind that their private information like text messages are safe, viewing the messages can only be done through the My Verizon account for each specific number. This is why you are only able to view the messages for the line your My Verizon account is signed up for.
To view the messages for the other 3 lines on your account, you would need to have access to the My Verizon accounts for those lines. If they do not have a My Verizon account, then you would need to register one for each of the lines. Keep in mind that you will also need those phones present to register.
Also, any lines that have iPhones would only show actual SMS and MMS messsages with us. Any messages between iPhones using iMessages, would not be recorded by us, since those would be processed by Apple's messaging services.
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