I don't use xapo wallet and so I would give you some options and if suitable try it at your own risk. See whether the transaction is free from xapo to another xapo wallet (some wallets support this feature). If it is supported then sell Bitcoins to someone who needs it. You can also try to convert it any other crypto currency such as DGB or ETH and transfer it to some exchange and use it for trading. If there is an option to withdraw the money to bank account then convert it into fiat and transfer it to your bank. You can also wait for the transaction fees to reduce over time and then make a transaction. The lightning network will be established soon and then the transaction fees will be reduced. So I recommend you holding the BTC as it is until the fee is reduced. If you are lucky enough the $50 worth BTC will be worth more than this until the fee is reduced
I'm not sure about transfer to anther persons xapo wallet i might look into that...
The only way to withdraw funds is through bitcoin no fiat withdrawal supported...
Xapo only supports BTC, no other cryptos...
They are doing my head in, i have contacted them multiple times and no response, only one automated response as a cover all to the 'large influx of complaints of the service' so obviously others are having problems with them too.
They are a shoddy service, i opened a small account with them years ago when i first got into bitcoin and always found the service poor.