Paperless Payroll Direct Deposit Stub Bulk Email not working properly with Office 365

Our company needs to send 250 check stubs and direct deposit stubs to our employees, we do that process 1 day per week and send all un Bulk, we use Sage 100 Advanced 2018 (Version 6.00.10.0).

Each week at least 20 emails have not been sent, we checked everything in Outlook 365 and it is like the emails never touch the server in the first place but, I was checking online and looks like office 365 have a cap of up to 30 messages per minute, so, is a way to create a delay in Sage so we can send all the paystubs using a delay per message and send all the messages properly?.

I already changed the configuration for the smtp connection in sage to outlook.office365.com | port 587 | smtp Encryption TLS/STARTTTLS | Use 128-bit Encryption for Password Protected Documents is checked.

Thanks!