This is likely fairly self-explanatory, and easy to fix.
It's been a problem for a bit, but figured I should report it, as it's obviously not triggering any errors with dev ops monitoring.
When fixing this error, perhaps a test to check that the Zoho Contacts interface successfully loads could be added.
This, along with unit tests to check a contact can be added, edited, deleted, etc might be considered an absolute minimum for any production code.