Access the Be Global Fulfillment system: https://globalfy.com/fulfillment/
Then, to be eligible to be merged both orders have to have the same shipping address.
You need to:
1) Go to order's details.
2) At the tab "Mergeable Orders" check the orders that can be merged.
3) At the "Set As Master" column, select what order will be the principal one.
4) Click on "Merge Orders".
If the orders are from EBAY the best way is not to do a merge because EBAY will not accept the same tracking number for 2 orders.
In the dashboard you will find the "Mergeable Orders" box with all the orders available to be merged.