A Bitcoin transaction that moves from pending to confirmed is always free. Don't worry if your recent Bitcoin transaction goes on pending or got stuck. Also, you might have not received a confirmation message. In times of network congestion, confirmation of transactions may take longer than normal. Your transaction would require a long time to get confirmed. The network may be clogged, therefore, all transactions take longer than usual. Hence, due to these reasons, transactions would be in the queue for many reasons.
