I had a breakdown issue in the Walmart parking lot. 04 Chevy Astro 2WD. Put $40 worth of gas in it and had about 1/2 a tank. Drove just fine and parked in the parking lot. Went in and did my shopping and came back out and gas gauge dropped to E, Miles left to E screen went to dashes, and fuel pump wouldn’t prime. Relay clicks when you turn the key on. Went and purchased a new fuel pump, dropped the tank, installed it, and swapped out the fuel filter. ECM-B fuse is good. Cleaned fuel pump ground above tank. Still not showing gas in the tank and still won’t prime. Also have a P0452 code, (Fuel tank pressure sensor circuit low voltage.) Another note, the day before it did the same thing on a slight incline. I put it in neutral and let it roll back and slammed on the brakes and it went back to normal. Didn’t work this time around. I’m completely stumped on what it might be.