Can I change the transaction merchant reference to the Order ID of Shopify?

Unfortunately, due to plugin limitations, it is currently not possible to display the Order ID generated by Shopify. The merchant reference number shown in the transaction tab of the Wallee Portal cannot be adjusted if you are using the Shopify plugin.

However if you are searching for a specific Order/Transaction you can simply use the following filters to narrow down the corresponding transaction: "Customer Given Name, Customer Family Name, Customer Email Address, Authorization Amount, Created On"

These filters can be viewed under Space -> Transactions:
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