The issue is likely being caused by the embedded font, not the plugin. Again, the plugin does not control or manage fonts.
Are you able to provide specifics for us to review, such as;
. Are there specific fields with the issue or are all fields having the issue?
. Is the issue related to specific words or characters?
. When the issue occurs on a specific merge, will the merge work when retried, or is the same entry always failing?
. Have you tried changing the embedded font?
We remain at your service.