Bitcoin unconfirmed transactions - what is the best solution to fast it up?
The simplest thing you can try is to rebroadcast the transaction and see if you get lucky. Here is one of the sites that offers this service http://www.speedupmybitcointransaction.com/

Failing that you can ask a mining pool for some help. For example ViaBTC offer a service described here https://www.cryptocompare.com/coins/guides/how-to-accelerate-your-bitcoin-transaction/

And failing that you can create a Child Pays For Parent (CPFP) transaction to increase the fee paid https://bitzuma.com/posts/how-to-clear-a-stuck-bitcoin-transaction/