Guild Wars 2

a couple days ago…
I recovered the email today and changed password to account and email, what more should I do to promise mine account security?
And he stole a couple things and some gold that I don’t really care about but there was like a 400 gems and he left only 8, can I somehow recover those gems or it’s a lost?

You should consider, if you didn’t, making a new email address solely for GW2 and using it for nothing else but GW2, then tie your account to that. Also add the authenticator if you can.

You should contact the support so they can restore your account the way it was just before the hack.

Contact support, they will be able to help you restore your account and gems.