how work POS? I have more whan 1200 NAV and wallet some days always open but more whan month not get stake

Why? buy more ? or
You must get 0,5 coins per day with 1200 coins!
But first do you unlock the wallet?
from: settings/unlock wallet (if you encrypt it in first place)
current version v2.0.7.0-UT-ZAH
p.s. ...o, and if you not have your wallet opened permanently, you will not get that percentage (less, depend on your luck)