Email Template Customizations being erased and replaced with default templates

I saw this other support post (https://projectdmc.org/support/topic/email-templates-are-not-working-3/#post-15918673) that had a very similar description to my error and it shows as resolved, but the problem is not resolved.

I am not trying to translate anything as was the case in the other post, just put in a new subject line and change the body of the email. It appears to work, and I can sometimes get the test email to send to me correctly, but then it will eventually blank it out again. I thought it was due to adding html comments, or syntax errors, but I am at a loss. It is resetting the template to the default (and/or erasing it from my editor window) at some point after doing a test email.

Any assistance appreciated. Thanks!

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The last few lines of my debug log says this:

[15-Aug-2022 20:46:05 UTC] PHP Notice:  Undefined index: subject in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 218
[15-Aug-2022 20:46:05 UTC] PHP Notice:  Undefined index: body in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 219
[15-Aug-2022 20:46:43 UTC] PHP Notice:  Undefined index: subject in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 218
[15-Aug-2022 20:46:43 UTC] PHP Notice:  Undefined index: body in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 219
[15-Aug-2022 20:48:10 UTC] PHP Notice:  Undefined index: subject in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 218
[15-Aug-2022 20:48:10 UTC] PHP Notice:  Undefined index: body in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 219
[15-Aug-2022 20:48:42 UTC] PHP Notice:  Undefined index: subject in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 218
[15-Aug-2022 20:48:42 UTC] PHP Notice:  Undefined index: body in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 219
[15-Aug-2022 20:52:03 UTC] PHP Notice:  Undefined index: subject in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 218
[15-Aug-2022 20:52:03 UTC] PHP Notice:  Undefined index: body in /home/customer/www/<example.com>/public_html/wp-content/plugins/paid-memberships-pro/includes/email.php on line 219

Plugin info:
Paid Memberships Pro Version 2.9.2 Updated: August 10, 2022
Paid Memberships Pro – Email Templates Add On Version 0.8.1`

 

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