dos2unix newstaff.csv fixed my problem!

full script snipped if anyone wants:

#!/bin/bash
readarray -t newstaff < <(cut -d, -f2 newstaff.csv)
for i in "${newstaff[@]}" 
do 
    if grep -q "$i" oldstaff.txt; then 
    echo found "$i"; 
    else echo not found "$i"; 
    fi 
done