Go to the Member tab -> Click the Member Profile -> Select Packages tab -> Click Add Package button ->  Select Invoice Date -> Select Back date -> Select Member Name -> Select Staff(If Required) -> Click Select Package -> Select Package -> Click Next button -> Give Discount(If Required) -> Click Next -> Select Payment Mode -> Click Submit Button -> The invoice will be raised.

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Go to the Transactions tab -> Click the Generate Invoice-> Select Invoice Date -> Select Back date -> Select Member Name -> Select Staff(If Required) -> Click Select Package -> Select Package -> Click Next button -> Give Discount(If Required) -> Click Next -> Select Payment Mode -> Click Submit Button -> The invoice will be raised.