Wierd demux quality score data using “Fastq manifest” formats, quality scores PHRED 33

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1

Hi,
I recently got Illumina-based 16s rRNA sequencing data.
I am trying to import my data using Fastq manifest format.
and the demultiplexed data is looking unusual.
"SingleEndFastqManifestPhred33V2" this variant was used to the procedure.
I am yet to finish the trimming process.but, when I am visualising it, the quality score graph looks weird.

why is it,
can somebody please assist me,
the quality score graph is attached below

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2

Newer Illumina machines do bin quality scores (scores that are close together get assigned the same score) which leads to these graphs being a bit flatter with newer Illumina machines than with other machines, but still the quality scores being completely flat like that is a bit unusual. It's possible that you just got a really good run.