How do I increase transaction fees in my Bitcoin wallet app?

I am using the bitcoin wallet app from bitcoinj.org. I sent a payment with a low fee, but it has been pending for 8 days. I sent a letter to the developer, but they only responded automatically. Below is what I got:

Q: My withdrawal hasn’t been confirmed for a long time.
Answer: The reason is the same as the previous question. The Bitcoin network is running at capacity limits. If you have time-critical payments as a sender, you will need to use Send Coins > Options > Fees > Priority to pay higher fees. Fees may increase even after transfer (Transaction > Options > Fee Increase). Know how much you spend on fees. Sometimes it’s more than you expect.

Now I can’t find a place to do that. When I click on a sent transaction, nothing happens.