2019 Toyota Sienna Engine Problems

I PULLED ONTO A HIGHWAY AND REACHING ABOUT 25 MPH THE 2019 SIENNA HESITATED FOR AT LEAST 10 SECONDS AS IF IT WAS NOT GETTING GAS. I PRESSED THE GAS WANTING TO GET OUT OF THE WAY OF TRAFFIC AND IT JUMPED SLIGHTLY BUT WOULD NOT GO. THEN IT KICKED IN WITH A FEW HESITATIONS AND TOOK OFF. ANOTHER 100' OR SO, IT DID IT AGAIN. PRIOR TO THIS I HAD ALREADY BROUGHT IT TO TOYOTA COMPLAINING THAT THERE IS A HESITATION WHEN THE VAN IS NOT WARMED UP YET BETWEEN 20-40 MPH. IT IS ONLY SLIGHT, BUT NOTICEABLE AND FEELS LIKE IT IS NOT GETTING GAS. THE VAN DOES THIS EVERY TIME AFTER IT HAS BEEN SITTING LONG ENOUGH TO COOL DOWN. THE LONG HESITATION ONLY HAPPENED TWICE SO FAR (DANGEROUS ENOUGH!), THERE HAVE BEEN A FEW SHORTER ONES, AND THEN THERE IS THE EVERY TIME SLIGHT HESITATION. TOYOTA HAS TOLD ME NOTHING SHOWS IN THEIR DIAGNOSTICS AND THEY DO NOT KNOW WHAT IS WRONG. THEY TRIED CUTTING THE POWER TO THE COMPUTER TO RESET THE MEMORY, BUT THIS DID NOT CHANGE ANYTHING.