I have exactly the same issue. It connected when first used but never again. I have paid the 18 pounds for support just to be told it is a hardware issue. I got the money refunded. I have advised HP that this is a common issue and that it is fair to say the fault was on the unit when purchased. I have been waiting for so called private message for almost 2 weeks and it came today. I will copy it at the end of this. Basically my sprocket is now 4 weeks out of warranty and they are not interested. I can't believe they won't help me in some way under the circumstances. 
Oh well. I'm not hard up for 100 pounds so can't be bothered to push it. HP on the other hand obviously are!!!
Good afternoon, Kevin
Thank you for taking the time to speak to me on Wednesday.
We have received confirmation that the amount you have paid to receive support has been refunded to your PayPal account.
Unfortunately, as your HP product is out of warranty, we are unable to further assist.
Thank you for your time and cooperation throughout this process and apologies for any possible inconvenience.