Bless your heart! That happened to us when we moved into our new home 10 years ago and our two boys were only 2 and 4 months old! I was worried about them overheating too, and it was miserable until someone could get out there. We just used big box fans and I let the kids play in cool water in the bathtub when I felt like they were gettint hot.
It’s miserable for the parents too! We live in Texas, so I can REALLY emphathize with you.
I hope it gets fixed soon!