Hi,
I'm not able to reproduce the problem on my end with the latest version of HikaShop.
This indicate that you have a fatal error.
It could be either some security component of your website/web server which falsly flag the delete request as potentially harmful or it could be a bug in HikaShop which only appears in some special case or a plugin integrated with it or another extension with a conflict.
So basically, it could be almost anything as that error message doesn't provide useful information. As the message says, to need to check the error logs (php error log, apache error log) to get the real error message behind that error so that we can better understand the situation.