Check the expiration date if you use the little dry yeast packets. I
found a lot of mine were mostly dead. I never did find out why they
were bad but I switched to a block yeast from the local baker.

I found that to get the specified rise in the time mentioned "warm"
meant 90 - 110 degrees.

I built a little proof box from an old mini-refrigerator and an old
electric frypan. Provides a good temp and humidity.

If you are proofing at room temp you should place a damp towel over the
pan to keep the surface of the dough from drying out.