If you have Person Account enabled in your Salesforce Org, by default, the layout will display Billing Address and Shipping Address. If you populate address into these 2 fields, the data will not be synchronised over to Saasu. To solve this issue, you need to:

1. Edit Person Account Layout
2. Remove Billing Address and Shipping Address from the layout
3. Add Mailing Address and Other Address to the layout
4. Populate Mailing and Other address information and this will be synchronised to the Saasu Contact.