Receiving an error code 315 when attempting to reinstall CoPilot or install it on a new device is an indication that the license you are using is currently assigned to another device.
To clear the error and reset the product key, please submit a request through the CoPilot Support Center. Type Error Code 315 in the subject line and include your product key in the description. You can find your product key in the app by going to Settings > About CoPilot.
Your request will be answered as soon as possible.