prefetch was handed a plain accession list, which it does not accept
prefetch takes either a single accession, or a kart file — the \"Cart File\" download from the SRA Run Selector. The plain SRR_Acc_List.txt is a different format and is not read as a list.
Loop over it one line at a time: while read acc; do prefetch \"$acc\"; fasterq-dump \"$acc\"; done < SRR_Acc_List.txt — and check the file's contents first, since a stray header line gets treated as an accession too.