@Kaieshiah
If you have changed your HDMI cables, tested on other TVs and still getting no signal, then most likely device issue failure.
Only other 2 suggestions I have is to make sure you are plugging the Roku device into a power adapter into the wall, not TV directly (if you haven't already) and try the final resort of a Factory Reset. (Using a paperclip, press and hold the Reset Button for 30+sec)
An underpowered device can lead to damage and premature failure. Other times, just luck of the draw and a bad device. Haven't seen many resolutions for this issue if both the power adapter use and factory reset fails to resolve it. (Of course, sometimes a bad power adapter can also contribute to issue, so any 5V, 1 amp power adapter can be used in its place).
Since you got your Roku Premiere for Christmas, you should still easily be covered by the 1-year warranty for device replacement offered by Roku. https://support.roku.com/article/208757058
Hope that helps.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102
