The transaction marked as unresolved can be resolved by clicking on the resolve button.
These statuses are used to categorize orders so that it is easier for the customer to differentiate between the orders which don't and which do need customer attention.
For example, If the transaction is received on the order address after the order is paid or the deadline expires, the order will become Unresolved. The user then has to decide for himself what to do in this case and select the command Resolved if she/he deems it necessary.