That fee is way to high for $50 when the blockchain is not congested. I think you used ETA on high priority that was why. Also maybe you have many little UTXO put together to make it $50.
As already mentioned by OmegaStarScream above your post, the fee doesn't depend on the amount you send at all.
If your transaction is from one UTXO, next time adjest the fee from the fee slider and use mempool.
What fee slider are you talking about?
I think you are talking about how to set the fee rate on electrum. OP didn't mention he used electrum.
There is now way to fix it because your transaction is already in the mempool waiting to be added to the blockchain by nodes.
Again wrong.
Transactions are not included in the blockchain by nodes. They are included in the blockchain by miners.
To OP:
You didn't tell us where did you make your transaction from.
As already mentioned by others, most non-custodial wallets allow you to set the transaction fee by yourself.
The transaction fee depends on number of inputs and outputs, types of addresses, how congested the network is and how fast you want your transaction to be confirmed.