Moss stitch is usually a multiple of 2. K1 p1 then on the following rows purl the knits and knit the purls (as they appear on the needle, not what you did to them on the next row). That's also called seed stitch in the US and the US moss stitch could be k1 p1 for 2 rows then p1 k1 for 2 rows.
Can you write out the stitch pattern that has you using a multiple of 2 plus 1? It may be that's not really moss stitch, or the extra stitch is a selvedge st.
sue- knitting heretic