Almost all transactions on Paxful exchange are made instantly. Transactions of Bitcoin are also made instantly.
In case the exchange is made via Bank Wire Transfer such as Western Union and Moneygram, then it may take a day or 2(or sometimes more) for the fund to arrive.
If you have made a such deal, you will get a notification from Paxful when the fund is arrived and the transaction is completed.
Exchanges via Gift Card or other Electronic Money are normally made instantly if there is no problem during the process.