An unconfirmed transaction is that transaction that has not been included in a block, and not completed also. Every transaction requires at least one confirmation to complete the transaction.

The common reasons for unconfirmed transactions are:

• You have made the transfer. The Bitcoin network needs at least 10 minutes to include the transaction in a block.
• The blockchain fee is very low. Thus, the lower the transaction fee, the lower your transaction’s priority in the Bitcoin network. Therefore, it takes longer confirmation to be a valid transaction.