My remote won't charge, I've followed all troubleshooting posted in other forms.
The remote is less than a year old, has never come into contact with water. Use same cable and charging block I've always used to charge it and have had no issues.
The back light flashes green, when I go to settings on the TV it says charging but remains at 0%.
The warranty on a new remote should be one year. Warranty claim instructions: https://support.roku.com/article/208757058. When it asks for the serial number, for remotes they say they want the serial number of the paired Roku device, not the remote.
I see many complaints of Voice Remote Pros that lose their ability to take a charge, but I have two of them, one for well over 2 years, and have noticed no loss of charge holding capacity or ability to charge. I don't know if I just happened to have gotten lucky and received good ones, or if my usage pattern has something to do with it.
Many (most? all?) rechargeable batteries deteriorate if repeatedly allowed to overcharge. Both my Samsung phone and Lenovo tablet even have optional features that will cut off charging before the battery reaches full charge to prevent or limit this deterioration. (I've suggested to Roku that they add this capability to their Voice Remote Pros, but the suggestion seems to have dropped into a black hole.)
From day one I've always made it a point to disconnect my Voice Remote Pros from the charger when they reach full charge, or slightly before. I especially try to avoid letting them charge unattended overnight. The charger I use outputs 2 amps and the remotes charge fairly quickly. The charge level can be checked via "Settings > Remotes & devices > Remotes > Voice Remote Pro > About" on the Roku. If I don't want to exit what I am watching just to check the charge level while charging, I just unplug the charge cord and observe the popup that usually (not always) appears on the upper right corner of the screen.