No. Once you confirm a withdrawal, it's processed and broadcast to the blockchain, and blockchain transactions can't be reversed — not by you, and not by Sykka. Once the funds leave your account, they're in the destination wallet, and only whoever controls that wallet can send them back.
This is why we ask you to review the address, network and amount carefully before confirming. Take a moment to check:
Address — matches the destination exactly. Compare the first and last several characters; copy and paste rather than typing.
Network — matches the network the destination wallet or exchange supports for that coin.