Multi Select Checkbox works in Acrobat but not Adobe Sign

I was able to get the multiselect checkboxes to work fine for acrobat documents.  You just assign the same name and different values to the checkboxes, but when I upload the document to adobe sign it seems to convert these checkboxes to radio buttons.  Is there anyway around this?  See example attached.  The left is the form in adobe sign.  The right is the same form in adobe acrobat.

Thanks,

Ben