If a customer has not submitted a form, what is the carrier's next step regarding mail delivery?

When a customer has not submitted a form regarding their mail delivery, the most appropriate next step for the carrier is to contact the customer for clarification. This action ensures that the carrier is abiding by postal regulations and maintaining effective communication with the customer. By reaching out, the carrier can verify the customer's current address and delivery preferences, helping to avoid any potential issues with undelivered mail. This proactive approach allows for improved customer service and ensures that mail is delivered correctly and efficiently.

Other options may lead to complications or misunderstandings. For instance, delivering to the old address could result in the mail not reaching the intended recipient. Holding the mail indefinitely would not be practical, as there are policies in place for mail retention and delivery. Returning it to sender might not be necessary if the carrier can simply clarify with the customer about where to deliver their mail. Thus, contacting the customer is the most responsible and effective course of action.