Write an article based on this "Open the Phone or Text app. Open a call or text message from the number you want to block. Tap ⋮. Tap People Options (text messages only). Tap Block Number."
If you wish to block a number from sending you voice calls, open the phone app.  If you wish to block a number from sending you text messages, open the text message app. It the Phone app, you can usually find a list of calls in the "Recent" list.  Recent text messages are displayed when you open the Text message app. It's the button with three dots in the upper-right corner of the call or text message.  This displays a drop-down menu. It's in the drop-down menu when you tap the icon with three dots in the upper-right corner. This blocks the number from your Android device.  Numbers blocked from the Phone app go straight to voicemail.  Numbers blocked from the Text app go to a separate folder.  If you do not want to receive voicemail or text messages from a number, use Methods 1 and 2 to block a number from your Sprint account.  Numbers blocked from your Sprint account are informed that you are not receiving calls when they try to contact you. To learn how to block a voice calls on iPhone, read How to Block a Number on iPhone.