You can turn Closed Captioning on and off on Roku from within the Hallmark Movies Now app
Closed captions can be turned on and off while watching
While playing a movie or series, pause the move and select the CC icon below the scrub bar.
Then you can switch the Captions to On, Instant Replay, On Mute, or Off. Press the OK button on your Roku remote to select an option.
Press the Back button on your Roku Remote to dismiss the menu and continue watching the film.
Adjusting Closed Captioning through the Menu
While playing a movie or series, press the * button on your Roku remote to open a sidebar menu.
Using the directional arrows on your Roku remote, toggle between On Always, On Replay, or Off.
Once you have toggled to your preferred option, press the * button on your Roku remote to dismiss the menu.
Roku provides instructions on managing the Closed Captioning settings for your device here: How do I enable closed captioning?