I am in a dilemma.

Suppose I brought stock 'A' at 80 Rs. and it went up to 90.

I want to add frequently through systematic investing considering further potential in the stock but the price has risen to 90. So should i add more at this price or should I add below my buying price which is Rs.80 in this case?

If i intend to go SIP in stocks should i ignore pricing?

Kindly advise.