And evaporation line is what happens when you read it after the suggested time frame .
Wait the 2 days and test again. @momma321 Possible it could be the indentation line as @cookiemonster1216 said.
Looks like an indentation line. Where the dye would be if it was positive. There isn't any color to it. If it were grey, I'd say evaporation line. But since it's no color, indent.
it said two minutes no more than ten. that was right after the two minutes