I've had this happen a few times recently where my modem drops and when it reconnects my static IP address is no longer there.
I've had the same static address with PlusNet for a very long time and rely on it for connecting to work PCs etc.
Any chance you can stick it back to the correct IP please?
Fixed! Go to the fix.
I'm really sorry to hear this has been happening and I apologise sincerely for the time it's taken to get back to you on this. I've had a look into this today with a colleague and we believe we've found the cause of the problem. We've made a couple of adjustments now which should fix the static IP address, you'll just need to reboot the router on your end.
Please let me know if it fixes it or not and I'll be happy to help should any further problems occur