500 server error when accessing some of my book collection stats

I get an error page on some of my book lists when trying to access the stats graphs. This used to work, but has been broken (on some of the lists) for a while now.

Currently working for me:
https://openlibrary.org/people/davidscotson/books/currently-reading

Currently not working for me:
https://openlibrary.org/people/davidscotson/books/want-to-read/stats
https://openlibrary.org/people/davidscotson/books/already-read/stats

### Evidence / Screenshot (if possible)

Error message recieved at url: https://openlibrary.org/people/davidscotson/books/already-read/stats
```
Sorry. There seems to be a problem with what you were just looking at.

We've noted the error 2023-08-17/111219748787 and will look into it as soon as possible
```
### Relevant url?

### Steps to Reproduce
I think this will only happen if you have certain items in your book list, so may be hard to reproduce unless there is some way to access my account or another that shows the is
sue.

* Actual: 500 server error with message quoted above
* Expected: The stats to display as the do for my 'currently reading' page

### Details

- **Logged in (Y/N)?** Yes
- **Browser type/version?** any/all
- **Operating system?** Mac but seems unlikely to be a factor
- **Environment (prod/dev/local)?** prod

### Proposal & Constraints
I'm assuming that it's data related, and possibly the error log that is mentioned will shed some light.

I'd originally assumed that it was a time-out issue when communicating with the Wikidata server, as the two that don't work have hundreds of items, and the one that still works much less. However, after taking a look at it, it seems the process doesn't even get that far, as it is all done in JS and the error seems to arise on the server before it gets to that point.

### Related files

### Stakeholders