Remote not controlling power or volume on my samsung tv anymore

Hi, Lmartin44 thank you for posting here in the Roku Community,

Thank you for reaching out and sharing your concern regarding the power and volume buttons on your Roku remote. We genuinely appreciate your patience as we work to assist you.

Could you please share if these buttons have functioned properly for you in the past? Additionally, if you could let us know when the issue first occurred?

In the meantime, we kindly suggest trying the following steps to see if they make a difference. 

1. Press Home on your Roku voice remote
2. Scroll and select Settings
3. Select Remotes & devices
4. Select Remote
5. Choose your voice remote from the list and select Set up remote for TV control
6. Follow the on-screen prompts to complete the process

NOTE: 

1. When you hear music playing, select Yes to confirm. If you do not hear music playing, try increasing the volume using your TV remote.
2. Next, your Roku device attempts to mute the volume using remote codes for the detected TV brand. If the music stops, select Yes.
3. If the music continues to play, select No. Your Roku device was unable to detect the correct information about your TV, however, you can manually enter the brand by selecting Enter TV brand.
4. As you enter the brand using the on-screen keyboard, a list to the right populates. After you select the brand, the music begins playing again. Select Yes when you hear it. As before, your Roku device again attempts to mute volume, this time using the first of multiple remote codes for the TV brand you entered. After each code is attempted, you are asked if the music stops playing. When it does, select Yes. 
5. Your Roku voice remote is now programmed to control both power and volume on your TV. Select OK to continue.

Please let us know if the issue is fixed or reply back to the thread for further assistance, we will be glad to help you.

Thanks,
Jharra