IkengaX

Hello very new here. I have 2005 maxima and it would appear that I am always running out of fuel. I have owned trucks so hauling a V6 is very familiar. I had a technician take out the fuel pump to test the gauge and its working fine so he decided to clean the tank as it was dirty only to discover that there was still a lot of fuel on the other half of the tank that didn't feed into the half that the pump is located. I need help, why isn't the fuel feeding back to the pump.

Many thanks