This happens in me someone steal my btc from my online wallet. What I did was I put 2fa since someone steal my btc, from that time I feel secured and no one got steal my btc. You should try to store it in xapo, its best wallet also.
Setting up 2fa verification is always suggested or must have because with this setting you will surely secure your wallet from any hacking attempts since they cant bypass a wallet without it specially when you do use online web wallets.Its advisable not to forget on enabling it just like mine even though I have small amounts of bitcoin better to secure it first so that no one could really steal It from you.Sorry for your loss op
