Hi Doug,
We regret to inform that the provided details are not enough to replicate the reported issue in our end. Could you please share the entire code blocks related to Spreadsheet and entire call stack for the reported exception? If possible, please share a sample to reproduce the reported scenario in our end. Or please have a look at the attached sample and modify the sample as per your scenario to replicate this issue. It will be more helpful for proceed further properly.
Regards,
Dhanasekar M.