Hi Marisa,
I linked the app in the first message: https://share.streamlit.io/chainleft/nft.observer/main/nft_history.py
As for the log file, Charly said “You’ll see the error trace if you click at the bottom right of your streamlit app.”
But this is what I see: 
image2068×1146 107 KB

Clicking at the bottom right on that crown symbol takes me to cloud page.
Otherwise there’s nothing else to click at the bottom right.