I ran spades with this command line
./spades.py -k 21,33,55,77,99,127 --careful --only-assembler -1 11-0910_S7_L001_R1_001.fastq.gz -2 11-0910_S7_L001_R2_001.fastq.gz -o 11_0911
and at the end
======= SPAdes pipeline finished WITH WARNINGS!
=== Error correction and assembling warnings:
* 0:00:04.945 4M / 8M WARN General (dataset_processor.cpp : 256) Failed to align paired reads /Users/apple/Desktop/SPAdes-3.6.2-Darwin/bin/11-0910_S7_L001_R1_001.fastq.gz and /Users/apple/Desktop/SPAdes-3.6.2-Darwin/bin/11-0910_S7_L001_R2_001.fastq.gz
What should I do next ?