Hi Kathryn, 

Thank you for your questions.  There can be multiple reasons you bread may not rise a second time.  Try correcting the reasons below and see if that helps.  If you need further assistance please reach out again.

Instant yeast vs active dry?  I would try using active dry yeast.  Sometimes the instant yeast works so fast that it will not give you a second rise, though it's supposed to. I would start with that first as well as looking at the other factors below that might affect the second rise.  

Old Dead Yeast. Dry, inactive yeast can live for years if kept at the right temperature. But if you used a packet of yeast found hiding in the back of the refrigerator, chances are it is dead. You might even buy a brand new package of yeast and find out that it is dead. Yeast that has been stored in a hot warehouse or submitted to fluctuating temperatures may be dead too, no matter how recently it was purchased. Don’t automatically assume you did something wrong, it could be as simple as dead yeast.

Yeast Is Too Hot. Recipes that call for active dry yeast direct you to dissolve that yeast in warm water. Sometimes the recipe calls for the liquid to be heated with fat and then added to the yeast. Either way, if the liquid is too hot it will kill off yeast cells. Yeast is pretty picky. It doesn’t like it too cold and it doesn’t like it too hot. Invest in a kitchen thermometer so you can test the water temperature next time.

The Room Is Too Cold. As mentioned above, yeast prefers a narrow temperature band, usually between 75 and 90 degrees Fahrenheit. There is a little wiggle room on either side, but not too much. So if the dough sits too long in a cold room, the yeast will eventually die. Many of us experience this in the winter when it’s nearly impossible to keep the kitchen at 75 degrees. You can set the rising dough in a warm place, like on top of the refrigerator or in a gas oven that has an always-on pilot light. I usually turn my electric oven on preheat for just a minute or two, turn it off and let the bread rise in the oven. Just don’t forget to turn the oven off before adding the dough! And don’t forget to remove the dough before heating the oven for another reason. 

Not Enough Time To Rise.  Rising dough takes time. Maybe longer than you you may expect. A longer rise time could be due to a room that is a little too cold or it could be that most of the yeast was dead. It could be because you are using a different kind of flour, or whole grain flour. Even sweet bread dough takes a long time to rise. If the dough hasn’t risen as much as you expect give it more time. Besides, a slower rise results in a more flavorful bread.

The Wrong Size Pan. Sometimes it isn’t that the dough didn’t rise, but that it doesn’t look like it rose. Usually it is because the pan is too large for the amount of dough. Use this rule of thumb for the best size pan:

• A recipe with approx. 3 cups of flour is perfect for an 8-1/2 x 4-1/2 inch pan.
• A recipe with approx. 4 cups of flour is perfect for a 9 x 5 inch pan.
• A recipe with approx. 4-1/2 cups of flour is perfect for a 10 x 5 inch pan.

I know you said you are using the correct pan size but still wanted to give you that information.