Weird error plot with doubtful taxonomy

[Varun9599]

Hello @benjjneb ! Hope you are well. I am currently running 2x300 PE samples on DADA2. Quality score looks good and doesn't drop below 30. Although, I observed an atypical error plot with sudden drops. (Attaching below) On top of that, the taxonomy assignment was really weird with names that we have never seen in our kind of samples. Can you please help me understand the problem? We have recently shifted from 2x250 to 2x300. Did not face this issue in our 2x250 data.

Thanks and Regards, Varun