Don't know what is causing this error?

If I remove the following code, the error doesn't get shown.

Why is this part of the code causing this error and how can I resolve it?

      <div className="relative flex flex-col items-center pt-[85.25%] sm:pt-[56.25%] md:pt-[56.26%]">
        <ReactPlayer
          className="absolute top-0 left-0"
          url={`https://www.youtube.com/watch?v=u5-CF_k0KK0&list=RDu5-CF_k0KK0&start_radio=1&ab_channel=TumpyGFX`}
          width="100%"
          height="100%"
        />
      </div>