Enterprise Rent-A-Car

I reserved a full size car from 9-4-21 to 9-6-21 and checked in on 9-2-21 and received a confirmation by email. When I got there they didn't have any full size cars available. Though they could upgrade the car to a compact SUV, Hyundai Kona, the trunk is much smaller than a full size car, like Camry or Sonata. I had many kids stuff, such as kids bike, wagon, chair, which I couldn't fit all in the Kona. They told me I can upgrade to a larger car but with $29/day extra charge. My itinerary was scheduled so I couldn't cancel it. I had to take the larger car and paid additional charge. I think it was not fair to me as it was not my mistake. It was not subjective to me to upgrade the rental.

Rental agreement is 4BLBNS.