Hello!
Thanks so much for taking your time to solve this. As you can see in the attached screenshot, the lab instructions on Step 23 indicate that sum1 should be used.
But you are correct, using sum2 solves the issue.
If you are able, could you please take a look at my post on 6/14 entitled: Lesson 7.3 PDF Extraction Not Working
I would really like to demonstrate this skill to my students.
Thanks!