My streaming device did an update and now doesn't function. Only the homepage, return and left arrow buttons worked. The OK (enter) button didn't work at all. Tried to do a reset but couldn't get the enter button to work there, either. Finally did a manual factory reset with the button. After it reactivated I found that I could not select my wifi signal to re-enter it or do anything else.
According to the website, my device is not eligible for agent support.
I think I would just try and eliminate a defective remote as the culprit.
You can purchase a new Voice Remote or even an inexpensive IR based universal streaming remote compatible with Roku devices at Walmart, Best Buy, Target, etc. (the IR remotes will not work with Streaming Sticks, but will for the Streaming players).
If the new replacement remote works, then you know you just have a bad remote.