[Koha] Problem with email notices

[King, Fred]

Esteemed Koha colleagues,

I recently set up overdue notices via Gmail. Everything seems to be going well except for one thing. I have Koha set up to send a friendly reminder on the day the item is due. For example, Schooner got this message (condensed to save space):

Dear  Schooner,
This is a friendly reminder that the following item(s) you borrowed from the library is/are now due:

"Bellevue "
by Oshinsky, David M.
WX 28 .O82 2017
Barcode: 32975000764287

(If the title, author, etc. are blank, please disregard this notice. We're trying to figure out why this keeps happening.)
Please return as soon as possible, or contact the library at 202-877-6221, or at WHCLibrary at medstar.net<mailto:WHCLibrary at medstar.net> if you would like to renew it. (Note that reserve books cannot be renewed except under special circumstances.)
For after hours returns: There is a book drop in the hallway outside of the library (2A43)
Thank you very much for your prompt attention to this matter.

Note: Schooner is my dog, who has no reasonable expectation of privacy regarding her book borrowing, so I can identify her by name.

The following day, she got another message:

Dear  Schooner,
This is a friendly reminder that the following item(s) you borrowed from the library is/are now due:

""
by

Barcode:

(If the title, author, etc. are blank, please disregard this notice. We're trying to figure out why this keeps happening.)
Please return as soon as possible, or contact the library at 202-877-6221, or at WHCLibrary at medstar.net<mailto:WHCLibrary at medstar.net> if you would like to renew it. (Note that reserve books cannot be renewed except under special circumstances.)
For after hours returns: There is a book drop in the hallway outside of the library (2A43)
Thank you very much for your prompt attention to this matter.

This is happening with every friendly reminder that goes out. It's not happening with any other notices, and it's using the same template for the reminder and the blank one.

Is this happening to anybody else? Does anyone have suggestions on how to fix it? I'm stumped.

--Fred

Fred King, MSLS, AHIP
Medical Librarian, MedStar Washington Hospital Center
fred.king at medstar.net
202-877-6670
ORCID 0000-0001-5266-0279
MedStar Authors Catalog: http://medstarauthors.org

I usually don't brag about owning expensive things, but I just left the grocery store.
--Anon