Invalid ABN error message when trying to lodge BAS from MYOB to the ATO directly

My client has received the following error when trying to lodge their BAS from MYOB:

 

"For the next step, we need your ABN.

We’ve detected that you haven’t entered an ABN, or the ABN you entered isn’t valid.

Please enter a valid ABN in the Company Information window or Business Settings page. Once you’ve done that, refresh this page."

 

The ABN is correct, the branch number is correct, the business name and trading name is correct. Not sure what else to try? 

 

Can anyone assist with this?

Thanks, Hannah