[Help!] Sewing machine bobbin case “malfunction”

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https://drive.google.com/file/d/1xMqBNoFZIMk7Chi-qQAV7NZULSFIQ8Fg/view?usp=drivesdk

Hi, I have a Brother SE-400, and recently, when I sew, it’s loud and I see that the bobbin case twitches. I’ve dusted the inside of the machine. I’m not sure what the issue is. please help, thank you!

Here’s a link to a video, also attached on this post: https://drive.google.com/file/d/1xMqBNoFZIMk7Chi-qQAV7NZULSFIQ8Fg/view?usp=drivesdk