I appreciate you taking the necessary steps to help resolve the issue, Ailoilo.
In QuickBooks Desktop, the Combine forms to a recipient in one email feature allows you to send these entries without losing the email information. This unusual behavior may require the program to be updated to help rectify issues within the system.

However, if the issue still persists, I recommend contacting our Live Experts Team to help review your account and provide further guidance so you can send these forms in one.
- In your QBDT account, go to Help and select QuickBooks Help/Contact Us.
- Choose Contact Us and enter a brief description of your issue. Then, Continue.
- Sign in to your Intuit account, choose Continue, and then Continue with my account.
- We'll email you a single-use code. Enter your code and select Continue.
- Then, select to Chat with usor Have us call you.
We’ll keep this thread available anytime you require further assistance.