This is so frustrating. I updated my Samsung tab s to lollipop earlier this month. It meant I had to register it as a new device for virgin tv anywhere. Why i have to do that I have no idea as it is the same device. Now I have no more changes for the month. Sky sports and movies now tells me the device is not registered and I have no more changes so I cant watch sky. I can however watch virgin tv anywhere and it shows as my device being registered. Why should I have to wait until next month to be able to change the device to watch what I pay for. Utter rubbish. I could understand if it was a different device but it is not.
Sorry to hear that your getting error of device limited reached on Sky Sports & Sky Movies due to an update to Lollipop.
Unfortunately when this does happen on any device, an update to the Operating System the TV Anywhere or Sky apps thinks its a new device. I know its frustrating as it happened to me and I had to wait for the new month to change my phone over.
However when I checked your account, it is showing you have one available change for both TV Anywhere and Sky. You should be able to now delete the device and re-register it.