Marketo not fetching Owner Id from SFDC

Hi there,

We don't use assignment rules in our SFDC and we have our lead settings to one default lead owner that will kick in when there is no lead owner.  The screenshot below:-

While using auto-assignment rules in the sync to SFDC flow step, I can see that the lead is successfully inserted in SFDC but on task creation step I am getting this error " Failed: no owner specified for lead id *******". 

As i further see the sync step i see that there is no owner id being fetched during this sync process. 

On checking with our SFDC admin nothing major has changed from the SFDC side that will impact any owner assignment. Please advise. 

Thanks