If you provided a cryptocurrency withdrawal address that is invalid:
If you have entered a wallet address that is incorrectly formatted or belonging to a different type of cryptocurrency, there is a chance it will be rejected and the transaction never happens. However, there is also a chance the transaction will go through - if this happens, it is most likely that your funds will be lost permanently.
If you provided a cryptocurrency withdrawal address that is valid but is not yours:
Blockchain transactions are irreversible. The only way you can get your cryptocurrency back is to contact the owner of the withdrawal address to return it back to you. If you cannot contact the owner, or if the address has no owner, your funds are irretrievably lost.
Therefore, we highly encourage you to be very certain of your withdrawal address for your cryptocurrency transactions. It is advisable to use copy and paste methods when trying to input your wallet address.