Hi Maurixx,
Sorry for the delay in response. Can you please let me know if emails for the admin were working fine before updating the plugin to v1.7.3?
If yes, can you please follow the instructions shared below to ensure they start working again?
In a scenario where email templates have been customized, please note that the templates provided in the plugin have been updated in v1.7.3 to ensure compatibility with YayMail Pro plugin. The customized templates need to be synced with the latest changes. The steps for the same are as follows:
1. Rename your customized templates (instead of deleting them so u can refer to them if needed in step 3).
2. Copy the templates again by going to WooCommerce->Emails->Email template name->Manage
3. Make the customization changes again and test if things work fine.
4. Once things work fine, please delete the old templates.
Please let me know if this helps.