Xbox Sequence X – Fortnite, glitchy graphics & bouncing FPS? : xbox

I acquired a recharged Xbox collection x from Gamestop at this time, and once I downloaded Fortnite – that is what it appeared like. I’ve tried reducing the graphics & modified out the HDMI. Fortnites the one sport I at the moment have, im downloading Sea of Theives & Fallout 4…although idk if that is one thing that results X|S Optimized video games? The FPS maxes at 60 (I believe thats all my TV can deal with) however fluctuates quickly, dropping and rising sooner then I can learn the numbers Thanks prematurely