Custom Exception message does not show

[feho1]

Hi, everyone.
I hope i can get help with problem I have.
in hookActionObjectCustomerUpdateBefore 
I have something like this : 
public function hookActionObjectCustomerUpdateBefore($params)
{
throw new PrestaShopException('You can not do this',999999999999999999); /// NOT WORKING 
throw new Exception($this->displayError("You can not do this"), 110); // NOT WORKING
}
None of them works I tried with $message = "you cant do this" same, tried without code, added documentation @throws exception and everything but all I get is : 

An unexpected error occurred. [PrestaShop\PrestaShop\Core\Domain\Customer\Exception\CustomerException code 0]

or

An unexpected error occurred. [Exception code 110]
 

Tried $this->context->controller->error[] 
did not work because it just goes and updates the info of customer.

Can anyone please help?