From Address always changes to default

Hi, When we send a Broadcast, we enter a From Email but it always changes back to the default Word Press email (Webmaster@CrpcPrograms.org). In General Settings of the Email Subscribers Plugin, we left the From Email Address blank and we use the email above for the admin email address.

We saw from another topic that a SMTP plugin could be changing the from address when we broadcast. In our case, we are using SendGrid but the From address in SendGrid is using a different email (Webmaster@cr-pc.com) so it appears that SendGrid is NOT changing the from address.

Any help at all would be appreciated. Thank you!