The fwd deck gun absent in the fo'cstle ,hence can not be a corvette or a frigate.
Position of the flag mast indicates it is not the Tripartite class minehunter of Pakistan navy.
Absence of winches in fwd deck indicates, that it is not a Fuqing class replenishment tanker.
size of the bridge(too big) for this vessel to be one of the missile boats.
And it looks like, this vessel is sailing sea state 8-9.
So I don't think it is a PN ship.