Sourdough fails on second proof
I have attempted making sourdough bread three times in the last week and a half. The first time, the starter failed, due to tap water and temperature. The latter starters I have made I used both rye flour and un-bleached AP flour separately. They rose and responded like gang busters! I fed them and they grew very well. Three times I have mixed the pre ferment and it did poorly the first time ( I think from temperature). The second time, I got through the pre ferment and tried to raise the total mixed dough. It sat in a warm spot for 10 hours and did nothing and I set it on a pan of warm water and it took off, but then wouldn't get the second proof or rise. The third time, Everything went well until the final proof and I am still waiting on the rise and to avoid cooking the dough, I am setting it on a thermostatically controlled heating pad. What am I doing wrong???