First, suggest you edit your post to remove email address. This is a public forum and spammers cruise places like this collecting publicly posted email addresses. Click the 3 vertical dots at upper right corner of your post to find edit option.
You don't say if this is a Roku device connected to a non-Roku tv, or a Roku TV with Roku built in.
Look for a tv control called Picture size, Zoom, or something similar to see if this is something you can adjust on the tv.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Streaming Stick 3600
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