Pyros weapon substat roll system

[Rasler_Heios]

Hi!
Could someone please explain to me how the substat roll system for the Pyros weapon works? I started with my WAR weap a few days ago and have rolled maybe 5-10 times so far. Yesterday, I finally got a second row on my weap, but today when I rolled again my substat was reduced to one row (changed from 80 crit and 110 SkS to 295 SkS).

I tried asking for help in the shout chat in Pyros, but the answer I got was that I should just keep rolling until I get 5 rows. But, how am I supposed to do that if I lose rows...?

(I am not a native english speaker, so I might have missed some important information, when I try to google guides I just get more confused,)

The way I did it is I started with 1 line of stat. The moment I got two lines with different attributes, I accepted it no matter what the values and attritbutes are. After i accepted the 2 lines, I then always get 2 lines when I roll. So I keep rolling until I get 3 lines with different attributes, I accepted it no matter what the attributes and values are. After I accepted the 3 lines, then I always get 3 lines when I roll. And then I repeat the same principle and process until I got 5 lines.