The broker does this when they think there is manipulation going on on the pps. They are watching the stock because to them they consider some unusal activity on the stock.
I think it wouldnt hurt to let PTSC know. But not sure they can do much.
I have seen this happen on some other OTCB stocks. The best thing you can do is change brokers. I cant stand that they do that.....it changes the "market" of the stock....