Importing from Express Invoice to Express Accounts Plus

[Stanik's Mower Service]

6/9/18 we Purchased updated versions of Express Accounts Plus and Express Invoice.  Previous information was lost so I started a customer base and Invoice information entered in Express Accounts Plus.  An employee entered new customers in Express Invoice.  I went to import the information into Express Accounts and now the customer/invoice base in Express Accounts is gone and the two new customers that were entered into Express Invoice are imported and that is all that is showing on Express Accounts.  I cannot find support to explain how the two programs work together.  When ordering Express Accounts Plus, it was recommended that Express Invoice be added to purchase.  Please explain.  Thank you.