Battery life will vary based on usage. For normal use, the remote batteries may last two months or longer. Does your Roku remote support private listening? This may also be one factor for the battery drain.
Please reply here with the serial number of your Roku device associated with the affected remote. It can be viewed by navigating to Settings > System > About.
Re: Roku Ultra 2020 remote is draining batteries within 3 days
Hello, I am having the same issue. Batteries drain to 0% in about 2 to 3 days. This is the second Roku Ultra purchase. I returned the other one due to the issue, hoping that purchasing a new one would fix the issue. However, I still have the same issue.