if I've created account/wallet on coinbase or any other exchange then my account is hacked and my coins/money lost who are responsible for it
The Exchange where I've created account

is it my mistake

what's you thought about it

and how i make my account safe

Actually good and bad people are every where so anytime your account may be hacked. But it is so taff to hack your wallet if you do not give your personal key or hacked your personal key. you have to all attempts to secure your account and if you do not do this you are responsible for your account hacking.