You could try to either 1) double spend the transaction with a higher fee (Replace-by-Fee) or 2) since you have also access of the recieving address, CPFP (Child pays for parent).
1) Quite a few wallets have this function build in. Bitcoin core and electrum for example.
You could import your private keys into one of these wallets and 'replace' the old TX.
2) If you plan going for CPFP then you basically have to create a new transaction spending those unspend outputs.
From either the address you sent the btc to or the change address (if you didn't send the whole amount). Make sure to include a fee which is high enough to cover the size of
both transactions. You can look for an estimated fee here:
https://bitcoinfees.earn.com/.