This article helps troubleshoot making or receiving calls on your HTC Desire 510.

You may have issues with calls if you have:

• A low signal strength
• Trouble making or receiving calls
• Frequently dropped calls

These steps help identify and resolve the underlying cause. After completing each step, test to see if the issue is fixed. If not, continue to the next step.

1. Verify airplane mode is turned off.

   1. Press and hold the Power key.
   2. If Airplane mode is ON displays, tap Airplane mode.

2. Verify your HTC Desire® 510 is connected to the Sprint voice network using Sprint Zone.

   Be sure your HTC Desire 510 is connected to the Sprint voice network to make or receive calls.

   1. From the home screen, tap the All Apps icon, then tap Sprint Zone.
   2. Swipe to the left to open Device Diagnostics.
   3. Look for Voice Network:
      • Voice Network is in the Passed section: Your phone is connected to the Sprint voice network.
      • Voice Network is in the Failed or Flagged section: Update the PRL.
      1. From Device Diagnostics, tap Voice Network.
      2. Tap Network PRL.
      3. After the update is complete, tap OK.

3. Verify if coverage is available at your current location.

   If your HTC Desire 510 has low signal strength, see if your location is within Sprint voice coverage on the Sprint coverage map.

4. Perform a soft reset.

   A soft reset reconnects your HTC Desire 510 to the Sprint network.

   1. Turn your phone off.
   2. Remove the battery. After 10 seconds, reinsert the battery.
   3. Turn your phone back on.

Note: To optimize device performance, be sure your HTC Desire 510 is running the most recent device software. Check for software updates.

If you're still having issues, dial *2 on your phone or dial 855-639-4644 to reach Sprint Prepaid Customer Care.