Cast off end of row

I can’t figure this out, sweater says cast off 5 each edge next 2 rows, everytime I try to cast off at the end of my row I have a huge space from cast off then 1 stitch I have no idea what I’m doing wrong. Please help

You cannot cast off stitches at the end of a row. Are you sure it doesn’t say to cast off 5 sts at the beginning of the next two rows?

Yes, cast off at the beginning edge.