cut bases before adapter

Hi, I met an uncommon problem that makes me at a loss, I opened my fastq file and search my adapter sequences in it, and I found there are base(s)before my adapter (and it’s not my barcode sequences), what’s worse, these bases are not equal in length which make it difficult to cut them, is there any way to deal with it?
The picture below is a screenshot of my fastq file, and the adapter sequence is highlighted.

correction: I mean primer sequences by saying adapter sequences

You can simply run cutadapt. Any extra bases before the primers will be trimmed off. If you search the forum you’ll find quite a bit of information on various ways to use cutadapt. For example:

-Mike