Intermittent Stalling (dealership no help)

I have a 2007 Toyota Prius & need some advice. I am the 2nd owner & purchased in 2009.
I’ve done all the regular/recommended maintenance & never had any issues until 2019.

2019 (120,001 miles): the maintenance light was on so the car was due for an oil change, I fueled up before driving over Mt. Hood (in OR) & made it about 60 miles up the mountain when all the warning lights came on (red triangle, hybrid warning light, etc.) & the car wouldn’t drive. I had the car towed to the dealership & they said I ran out of gas & it was due for an oil change. I drove it home the next day (about 130 miles) & had no issues for 2 years.

2021 (133,831 miles), same scenario: the maintenance light was on so the car was due for an oil change, stopped for fuel (my boyfriend was with me luckily so I had a witness that I put fuel in), started driving over Mt. Hood & made it slightly further when the car gave the same lights - this time also giving the “low fuel” light, we tried but the car would not take more fuel.

Coasted down the mountain & made it to town. Once it sat idle for a few hours it started “normally” but got the same errors soon after so towed it home.
The next day we read it could be from a bad 12v so we replaced the 12v battery & didn’t have any issues - until 2022.

2022 (139,648 miles), similar scenario: the maintenance light was on so the car was due for an oil change, stopped for fuel, driving a long stretch of hills when the same errors came on & the car stalled. Towed it home. The next day it started normally, drove it to the dealership & they said the only code was “ran out of fuel”. Had them do an extensive inspection & they said it needed the serpentine belt changed (done), oil change (done) & transmission flush (done).

Neither dealership has been able to tell what’s actually wrong with the car, only saying it’s run out of fuel - which isn’t possible, since it’s just been filled up each time.

Has anyone encountered this? Would the fuel pump/fuel filter assembly and/or bladder tank be responsible for these intermittent stalls? Any guidance would be greatly appreciated.
Thank you in advance for your time!

 

2019 I can’t be sure the gallons but I see the charge on my bank statement and it was $14 so probably around 4 gallons.
(I was thinking even if that’s all the gas it had in it, I should have been able to drive 150 miles or so before it ran out.)

2021 & 2022 put between 5-7 gallons in, I watch each time they pump now because I’m paranoid.

You are correct, the only code they got was “out of fuel”.
The only mechanic around that works on a Prius wants $2,500 to replace the fuel pump & I don’t even know if that’s what’s wrong. So figured I’d ask for any advice first. Thanks!