The electrical contacts under that button have likely gotten dirty. Some handy folks can disassemble and repair but for most of us it just means getting a new remote.
You can purchase from Roku (https://www.roku.com/products/accessories) or many retailers.
Meanwhile, if you have an Android or iOS mobile device with WiFi, you can use the official Roku Mobile app to control your Roku.
https://www.roku.com/mobile-app
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
Ultra 4800 | Streaming Stick 4K+ 3821 | TCL Roku TV 43S245/C107X
