What is a one-sentence summary of the following article?
You can use any web browser on PC, Mac, or your mobile phone. Use the spaces provided on the web page to type the username and password associated with your Sprint account.  Then click Submit.  This logs you into your Sprint account on the website. If you do not have a sprint account click Sign Up on the right side of the screen.  You must have service through Sprint to sign up for an account. This displays menu options for your Sprint account. It's in the "My Sprint" menu options. There may be an authentication process.  Have your account details ready and answer any questions to confirm your account. This displays a list of blocked numbers. This displays an options menu next to the number. To unblock all numbers, click Do not block any voice calls.  This archives all blocked calls so you can find them later. It's in the menu that appears when you click on a blocked number.  This removes the number from the list of blocked numbers.    If you need assistance, contact 1-888-211-4727 to contact Sprint customer service.  If you blocked calls from your phone app (Android) or Settings menu (iPhone), see Method 1 to learn how to unblock numbers from your Android phone.  See Method 2 and to learn how to unblock numbers from an iPhone.

Summary:
Navigate to https://www.sprint.com/en/login.html using a web browser. Type your username and password and click Submit. Click My Sprint. Click Permissions. Click Block voice. Click the number you wish to unblock. Click Remove number.