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Find your most recent Sprint statement or agreement. Call 1-888-211-4727. Ask to speak to a customer service agent. Ask the customer service agent to block the number you specify. Turn your phone off and on.
Locate the account number. Customer service will need this number to view your account. This is the number to Sprint customer service. Listen to the automated voice system and follow the instructions to speak to a customer service representative. They will check to see if you have permissions to do so on your account and phone. The changes will be made in approximately 15 minutes.