Sorry to hear about the trouble. 

Here's a few tips that usually fix reader trouble:

- Check that your "device is supported":https://squareup.com/compatibility.
- Remove any case from your device. Some cases prevent the reader from plugging in completely. You should hear a click when the reader is fully connected. 
- Make sure you have the latest version of your device's operating system and the "Square app":https://squareup.com/help/article/4982. 
- Unplug the reader and plug it back in while the Square app is open and wait for it to establish a new session.
- If you see “Please try inserting again, chip could not be read," insert the chip card firmly with the chip facing Square’s logo.
- Plug the reader into a power source, leave it for 1-5 minutes, and then plug it back into the device. 
- Delete and reinstall the Square app. See "Apple":https://support.apple.com/en-us/HT201398 or "Google":https://support.google.com/googleplay/answer/2521768?hl=en support for instructions. Before deleting the app, make sure to "upload any payments taken while in Offline Mode":https://squareup.com/help/article/5095, or the funds will not be captured and the payments will not complete. 
- If you're using an *Android* device, make sure that any audio enhancement features (One M8, Clari-fi, or Beats Bass Boost) are turned off, as they can disrupt connection with the reader.
- If you've seen an error message, "*Register needs VoiceOver to be turned off*," go to your device settings and tap *General* > *Accessibility* > *VoiceOver* and turn off VoiceOver. This may also be called "S Voice" or "Talkback" on your device. If that doesn't do the trick, turn off *Mono Audio* from your device settings.

Hopefully, these tips do the trick. If you're still having issues, please let me know in more detail what's going on.