Linking supplier invoices to MYOB issue

I have received an email with an invoice attached that has a link in it to enable me to link that supplier to my MYOB file for automatic uploading of invoices.

I work with 3 MYOB files for different entities.

When I select "Link to MYOB" option on the invoice, it lists my 3 entities for me to choose which one to link to.  I want the 2nd option, but it will not link to anything other than the top option no matter what I do.  I select the 2nd option, it says it has linked, but the upload is in my first MYOB file - not the correct one that I just chose.

Is there something I need to do elsewhere to make it go to the option I choose?

Thanks, Glenn