Sending Email via API getting "SendEmailLimitReached" error.

Ok so after spending 2 hrs waiting for a support member I have found the problem and the solution, there is Email send limits on MOYB accounts, I am unsure what those limits are and if just for trial account or full production accounts etc I am still waiting for a response but the solution is meant o contact support and request the limits to be removed.

As stated by Business support said

"Thank you for holding and apology for the long wait. MYOB has a daily email sending limit. This security measure prevents malicious users from creating MYOB accounts to send high volumes of fraudulent invoices to other businesses."  

and later when asked about the limit 

"There is no specific amount of email it will automatically apply a temporary block on accounts that send a high number of emails in a short time."

So the solution is to contact support and request the removal of the email limit