Polydough flatness issue

If anyone could diagnose how my bread loaves go flatter in the oven I would really appreciate it

Sorry. My bread was the poly dough from Paul

What was the temp of the water when you added the yeast?

Did you test your yeast?

That would be my guess that the yeast did not work.

For others who might want to try the polydough:

https://permies.com/t/1371/kitchen/Poly-Dough-pizza-bread-fry

I'm not the polydough expert, but to me those pan loaves look the way mine get when the dough is a bit wet and overproofs (second rise is a little too long-- it gets way high and then falls during baking).
I've been baking for a jillion years and sometimes they overproof, and we eat 'em anyway! but you might want to try kneading in a bit more flour when you form the loaves, rising just until you see it's risen (not like leave it for 4 hours, like i occasionally do), and slicing it to get a nice ear.