Sand Slots help please

when i started the game i recieved lots of circle sand slots to be filled but only 3 filled with sand in the circle slots after fighting the pirates on the ship there are 6 or 7 to fill and i'm at the chapter 10 and still have only 3 filled after fighting and killing and running under the dead sands . now i use one for rewinding the time and still kill and can't get that one filled what is wrong. why won't the sand circles fill after i kill and run under the sand from the dead enemies. Only 3 is there for me why and when i use any of them can't get any back? Help [email protected]

Ure computers screwed

try to kill the enemies with throwing a sword or axe. that mostly results in a sand-cloud. Look also to some jars and barrels. when you smatter them a sandcloud could be present.
But it is normal to have only three circle's in the beginning of the game. Now after completing the activation of the mechanical tower I earned the fourth one at a time travel cloud.
Hopefully it will help you

in 60-70% game you will get all 6 tanks (from sands portals) be patient