Hi @blmirza,
In your Settings > Workflow > Emails area, under “Email Templates”, do you have an email template called ANNOUNCEMENT? For example (in French):
If not, create a new one. You can get the default subject, body, and description from the locale files: ojs/emails.po at 3_2_1-1 · pkp/ojs · GitHub
Make sure that the email key is ANNOUNCEMENT, so that OJS knows that this is the one to send when you create a new announcement.
Regards,
Alec Smecher
Public Knowledge Project Team