Got stuck, decrease on purl side?

I am having issues finishing up this pattern. Can help me please?

Here is my question, start from Row 13…
Row 13 : BO 5 at beginning (this should be knit side)
Row 14 : BO 5 at beginning (this should be purl side)
Row 15 : knit side
Row 16 : purl side (instruction seem to ask me to do the dec on this row, but this row is purl row. How do I follow the dec as K2tog at beg of row and ssk at end of row)??

[B][U]Here is the instruction…[/U][/B]

[COLOR=“Red”]Work dec as K2tog at beg of row and ssk at end of row.[/COLOR]

CO 70 sts.

Rows 1-11: Beg with knit row, work in St st.
Row 12: P20, place removable maker, P30, place removable marker, pur to end.

Cont in St st and AT SAME TIME work cap shaping as follows.
[COLOR=“red”]BO5 sts at beg of next 2 rows.
Dec 1 st at each end every 4 rows.[/COLOR]

Row 13-24: Work in St st.
Row 25: Join pleat on 30 sts between markers picked up on row 12. Remove markers.
Rows 26-35: Work in St st.
Rows 36

Thanks

You can begin the dec on row 15 and then continue every 4th row with rows 19, 23, 27 etc, all knitside rows.

thanks